Граф коммитов

914 Коммитов

Автор SHA1 Сообщение Дата
Linus Torvalds d987ca1c6b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull exec/proc updates from Eric Biederman:
 "This contains two significant pieces of work: the work to sort out
  proc_flush_task, and the work to solve a deadlock between strace and
  exec.

  Fixing proc_flush_task so that it no longer requires a persistent
  mount makes improvements to proc possible. The removal of the
  persistent mount solves an old regression that that caused the hidepid
  mount option to only work on remount not on mount. The regression was
  found and reported by the Android folks. This further allows Alexey
  Gladkov's work making proc mount options specific to an individual
  mount of proc to move forward.

  The work on exec starts solving a long standing issue with exec that
  it takes mutexes of blocking userspace applications, which makes exec
  extremely deadlock prone. For the moment this adds a second mutex with
  a narrower scope that handles all of the easy cases. Which makes the
  tricky cases easy to spot. With a little luck the code to solve those
  deadlocks will be ready by next merge window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (25 commits)
  signal: Extend exec_id to 64bits
  pidfd: Use new infrastructure to fix deadlocks in execve
  perf: Use new infrastructure to fix deadlocks in execve
  proc: io_accounting: Use new infrastructure to fix deadlocks in execve
  proc: Use new infrastructure to fix deadlocks in execve
  kernel/kcmp.c: Use new infrastructure to fix deadlocks in execve
  kernel: doc: remove outdated comment cred.c
  mm: docs: Fix a comment in process_vm_rw_core
  selftests/ptrace: add test cases for dead-locks
  exec: Fix a deadlock in strace
  exec: Add exec_update_mutex to replace cred_guard_mutex
  exec: Move exec_mmap right after de_thread in flush_old_exec
  exec: Move cleanup of posix timers on exec out of de_thread
  exec: Factor unshare_sighand out of de_thread and call it separately
  exec: Only compute current once in flush_old_exec
  pid: Improve the comment about waiting in zap_pid_ns_processes
  proc: Remove the now unnecessary internal mount of proc
  uml: Create a private mount of proc for mconsole
  uml: Don't consult current to find the proc_mnt in mconsole_proc
  proc: Use a list of inodes to flush from proc
  ...
2020-04-02 11:22:17 -07:00
Linus Torvalds 29d9f30d4c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Fix the iwlwifi regression, from Johannes Berg.

   2) Support BSS coloring and 802.11 encapsulation offloading in
      hardware, from John Crispin.

   3) Fix some potential Spectre issues in qtnfmac, from Sergey
      Matyukevich.

   4) Add TTL decrement action to openvswitch, from Matteo Croce.

   5) Allow paralleization through flow_action setup by not taking the
      RTNL mutex, from Vlad Buslov.

   6) A lot of zero-length array to flexible-array conversions, from
      Gustavo A. R. Silva.

   7) Align XDP statistics names across several drivers for consistency,
      from Lorenzo Bianconi.

   8) Add various pieces of infrastructure for offloading conntrack, and
      make use of it in mlx5 driver, from Paul Blakey.

   9) Allow using listening sockets in BPF sockmap, from Jakub Sitnicki.

  10) Lots of parallelization improvements during configuration changes
      in mlxsw driver, from Ido Schimmel.

  11) Add support to devlink for generic packet traps, which report
      packets dropped during ACL processing. And use them in mlxsw
      driver. From Jiri Pirko.

  12) Support bcmgenet on ACPI, from Jeremy Linton.

  13) Make BPF compatible with RT, from Thomas Gleixnet, Alexei
      Starovoitov, and your's truly.

  14) Support XDP meta-data in virtio_net, from Yuya Kusakabe.

  15) Fix sysfs permissions when network devices change namespaces, from
      Christian Brauner.

  16) Add a flags element to ethtool_ops so that drivers can more simply
      indicate which coalescing parameters they actually support, and
      therefore the generic layer can validate the user's ethtool
      request. Use this in all drivers, from Jakub Kicinski.

  17) Offload FIFO qdisc in mlxsw, from Petr Machata.

  18) Support UDP sockets in sockmap, from Lorenz Bauer.

  19) Fix stretch ACK bugs in several TCP congestion control modules,
      from Pengcheng Yang.

  20) Support virtual functiosn in octeontx2 driver, from Tomasz
      Duszynski.

  21) Add region operations for devlink and use it in ice driver to dump
      NVM contents, from Jacob Keller.

  22) Add support for hw offload of MACSEC, from Antoine Tenart.

  23) Add support for BPF programs that can be attached to LSM hooks,
      from KP Singh.

  24) Support for multiple paths, path managers, and counters in MPTCP.
      From Peter Krystad, Paolo Abeni, Florian Westphal, Davide Caratti,
      and others.

  25) More progress on adding the netlink interface to ethtool, from
      Michal Kubecek"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2121 commits)
  net: ipv6: rpl_iptunnel: Fix potential memory leak in rpl_do_srh_inline
  cxgb4/chcr: nic-tls stats in ethtool
  net: dsa: fix oops while probing Marvell DSA switches
  net/bpfilter: remove superfluous testing message
  net: macb: Fix handling of fixed-link node
  net: dsa: ksz: Select KSZ protocol tag
  netdevsim: dev: Fix memory leak in nsim_dev_take_snapshot_write
  net: stmmac: add EHL 2.5Gbps PCI info and PCI ID
  net: stmmac: add EHL PSE0 & PSE1 1Gbps PCI info and PCI ID
  net: stmmac: create dwmac-intel.c to contain all Intel platform
  net: dsa: bcm_sf2: Support specifying VLAN tag egress rule
  net: dsa: bcm_sf2: Add support for matching VLAN TCI
  net: dsa: bcm_sf2: Move writing of CFP_DATA(5) into slicing functions
  net: dsa: bcm_sf2: Check earlier for FLOW_EXT and FLOW_MAC_EXT
  net: dsa: bcm_sf2: Disable learning for ASP port
  net: dsa: b53: Deny enslaving port 7 for 7278 into a bridge
  net: dsa: b53: Prevent tagged VLAN on port 7 for 7278
  net: dsa: b53: Restore VLAN entries upon (re)configuration
  net: dsa: bcm_sf2: Fix overflow checks
  hv_netvsc: Remove unnecessary round_up for recv_completion_cnt
  ...
2020-03-31 17:29:33 -07:00
Namhyung Kim 6546b19f95 perf/core: Add PERF_SAMPLE_CGROUP feature
The PERF_SAMPLE_CGROUP bit is to save (perf_event) cgroup information in
the sample.  It will add a 64-bit id to identify current cgroup and it's
the file handle in the cgroup file system.  Userspace should use this
information with PERF_RECORD_CGROUP event to match which cgroup it
belongs.

I put it before PERF_SAMPLE_AUX for simplicity since it just needs a
64-bit word.  But if we want bigger samples, I can work on that
direction too.

Committer testing:

  $ pahole perf_sample_data | grep -w cgroup -B5 -A5
  	/* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */
  	struct perf_regs           regs_intr;            /*   312    16 */
  	/* --- cacheline 5 boundary (320 bytes) was 8 bytes ago --- */
  	u64                        stack_user_size;      /*   328     8 */
  	u64                        phys_addr;            /*   336     8 */
  	u64                        cgroup;               /*   344     8 */

  	/* size: 384, cachelines: 6, members: 22 */
  	/* padding: 32 */
  };
  $

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lore.kernel.org/lkml/20200325124536.2800725-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-27 10:41:44 -03:00
Namhyung Kim 96aaab6865 perf/core: Add PERF_RECORD_CGROUP event
To support cgroup tracking, add CGROUP event to save a link between
cgroup path and id number.  This is needed since cgroups can go away
when userspace tries to read the cgroup info (from the id) later.

The attr.cgroup bit was also added to enable cgroup tracking from
userspace.

This event will be generated when a new cgroup becomes active.
Userspace might need to synthesize those events for existing cgroups.

Committer testing:

From the resulting kernel, using /sys/kernel/btf/vmlinux:

  $ pahole perf_event_attr | grep -w cgroup -B5 -A1
  	__u64                      write_backward:1;     /*    40:27  8 */
  	__u64                      namespaces:1;         /*    40:28  8 */
  	__u64                      ksymbol:1;            /*    40:29  8 */
  	__u64                      bpf_event:1;          /*    40:30  8 */
  	__u64                      aux_output:1;         /*    40:31  8 */
  	__u64                      cgroup:1;             /*    40:32  8 */
  	__u64                      __reserved_1:31;      /*    40:33  8 */
  $

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
[staticize perf_event_cgroup function]
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lore.kernel.org/lkml/20200325124536.2800725-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-27 10:39:11 -03:00
Bernd Edlinger 6914303824 perf: Use new infrastructure to fix deadlocks in execve
This changes perf_event_set_clock to use the new exec_update_mutex
instead of cred_guard_mutex.

This should be safe, as the credentials are only used for reading.

Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-03-25 10:04:01 -05:00
Dan Carpenter a6763625ae perf/core: Fix reversed NULL check in perf_event_groups_less()
This NULL check is reversed so it leads to a Smatch warning and
presumably a NULL dereference.

    kernel/events/core.c:1598 perf_event_groups_less()
    error: we previously assumed 'right->cgrp->css.cgroup' could be null
	(see line 1590)

Fixes: 95ed6c707f ("perf/cgroup: Order events in RB tree by cgroup id")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200312105637.GA8960@mwanda
2020-03-20 13:06:22 +01:00
Peter Zijlstra 90c91dfb86 perf/core: Fix endless multiplex timer
Kan and Andi reported that we fail to kill rotation when the flexible
events go empty, but the context does not. XXX moar

Fixes: fd7d55172d ("perf/cgroups: Don't rotate events for cgroups unnecessarily")
Reported-by: Andi Kleen <ak@linux.intel.com>
Reported-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200305123851.GX2596@hirez.programming.kicks-ass.net
2020-03-20 13:06:22 +01:00
Jiri Olsa bfea9a8574 bpf: Add name to struct bpf_ksym
Adding name to 'struct bpf_ksym' object to carry the name
of the symbol for bpf_prog, bpf_trampoline, bpf_dispatcher
objects.

The current benefit is that name is now generated only when
the symbol is added to the list, so we don't need to generate
it every time it's accessed.

The future benefit is that we will have all the bpf objects
symbols represented by struct bpf_ksym.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-5-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2020-03-13 12:49:51 -07:00
Ian Rogers 95ed6c707f perf/cgroup: Order events in RB tree by cgroup id
If one is monitoring 6 events on 20 cgroups the per-CPU RB tree will
hold 120 events. The scheduling in of the events currently iterates
over all events looking to see which events match the task's cgroup or
its cgroup hierarchy. If a task is in 1 cgroup with 6 events, then 114
events are considered unnecessarily.

This change orders events in the RB tree by cgroup id if it is present.
This means scheduling in may go directly to events associated with the
task's cgroup if one is present. The per-CPU iterator storage in
visit_groups_merge is sized sufficent for an iterator per cgroup depth,
where different iterators are needed for the task's cgroup and parent
cgroups. By considering the set of iterators when visiting, the lowest
group_index event may be selected and the insertion order group_index
property is maintained. This also allows event rotation to function
correctly, as although events are grouped into a cgroup, rotation always
selects the lowest group_index event to rotate (delete/insert into the
tree) and the min heap of iterators make it so that the group_index order
is maintained.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20190724223746.153620-3-irogers@google.com
2020-03-06 11:57:01 +01:00
Ian Rogers c2283c9368 perf/cgroup: Grow per perf_cpu_context heap storage
Allow the per-CPU min heap storage to have sufficient space for per-cgroup
iterators.

Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-6-irogers@google.com
2020-03-06 11:57:00 +01:00
Ian Rogers 836196beb3 perf/core: Add per perf_cpu_context min_heap storage
The storage required for visit_groups_merge's min heap needs to vary in
order to support more iterators, such as when multiple nested cgroups'
events are being visited. This change allows for 2 iterators and doesn't
support growth.

Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-5-irogers@google.com
2020-03-06 11:57:00 +01:00
Ian Rogers 6eef8a7116 perf/core: Use min_heap in visit_groups_merge()
visit_groups_merge will pick the next event based on when it was
inserted in to the context (perf_event group_index). Events may be per CPU
or for any CPU, but in the future we'd also like to have per cgroup events
to avoid searching all events for the events to schedule for a cgroup.
Introduce a min heap for the events that maintains a property that the
earliest inserted event is always at the 0th element. Initialize the heap
with per-CPU and any-CPU events for the context.

Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-4-irogers@google.com
2020-03-06 11:56:59 +01:00
Peter Zijlstra 98add2af89 perf/cgroup: Reorder perf_cgroup_connect()
Move perf_cgroup_connect() after perf_event_alloc(), such that we can
find/use the PMU's cpu context.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-2-irogers@google.com
2020-03-06 11:56:58 +01:00
Peter Zijlstra 2c2366c754 perf/core: Remove 'struct sched_in_data'
We can deduce the ctx and cpuctx from the event, no need to pass them
along. Remove the structure and pass in can_add_hw directly.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-06 11:56:58 +01:00
Peter Zijlstra ab6f824cfd perf/core: Unify {pinned,flexible}_sched_in()
Less is more; unify the two very nearly identical function.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-06 11:56:55 +01:00
Thomas Gleixner 1d7bf6b7d3 perf/bpf: Remove preempt disable around BPF invocation
The BPF invocation from the perf event overflow handler does not require to
disable preemption because this is called from NMI or at least hard
interrupt context which is already non-preemptible.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.151953573@linutronix.de
2020-02-24 16:18:20 -08:00
Kan Liang bbfd5e4fab perf/core: Add new branch sample type for HW index of raw branch records
The low level index is the index in the underlying hardware buffer of
the most recently captured taken branch which is always saved in
branch_entries[0]. It is very useful for reconstructing the call stack.
For example, in Intel LBR call stack mode, the depth of reconstructed
LBR call stack limits to the number of LBR registers. With the low level
index information, perf tool may stitch the stacks of two samples. The
reconstructed LBR call stack can break the HW limitation.

Add a new branch sample type to retrieve low level index of raw branch
records. The low level index is between -1 (unknown) and max depth which
can be retrieved in /sys/devices/cpu/caps/branches.

Only when the new branch sample type is set, the low level index
information is dumped into the PERF_SAMPLE_BRANCH_STACK output.
Perf tool should check the attr.branch_sample_type, and apply the
corresponding format for PERF_SAMPLE_BRANCH_STACK samples.
Otherwise, some user case may be broken. For example, users may parse a
perf.data, which include the new branch sample type, with an old version
perf tool (without the check). Users probably get incorrect information
without any warning.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200127165355.27495-2-kan.liang@linux.intel.com
2020-02-11 13:23:49 +01:00
Linus Torvalds ca21b9b370 A set of fixes and improvements for the perf subsystem:
- Kernel fixes:
 
    - Install cgroup events to the correct CPU context to prevent a
      potential list double add
 
    - Prevent am intgeer underflow in the perf mlock acounting
 
    - Add a missing prototyp for arch_perf_update_userpage()
 
  - Tooling:
 
    - Add a missing unlock in the error path of maps__insert() in perf maps.
 
    - Fix the build with the latest libbfd
 
    - Fix the perf parser so it does not delete parse event terms, which
      caused a regression for using perf with the ARM CoreSight as the sink
      confuguration was missing due to the deletion.
 
    - Fix the double free in the perf CPU map merging test case
 
    - Add the missing ustring support for the perf probe command
 -----BEGIN PGP SIGNATURE-----
 
 iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl5AC0ITHHRnbHhAbGlu
 dXRyb25peC5kZQAKCRCmGPVMDXSYoaJtD/4jEdN6KNGVJIQ5jOYdchXK/zb68plS
 3By6CegbaNq1SU5UPIdMX4BkznVGaVtJU/0hWuvD/ycpBTAMgKjwalYJtAC+anVi
 JhG7NiPRV1Nhm+7eZ/78mUpW4CUimTlvZVzU/yneYdFm2klvcxUHblJYSqEGp0AS
 r2aZRsqQnWSoI/+z+0THO8tI+HLSpkmKy2slLxaZphI0VjSrjWPDHfF6eAOyl/dq
 lTCz+tjd6EytELL+lhWFsGXYAi6HPKP3T4yPRH+eDYKQmByYaEYbK3E8wg/0XB/J
 2AHgSBf9pSPDBIkLOWOidmkmWgZD9ykCTyOPu4N0S70+NeaCm2nXLTOQ7dnyLE7t
 WCx8mvnIS2hshNUoXMkarG5LYexPupDMMEfHyUT5+T2rKxacKWLaRoIV+JCsUpQb
 m6eU3+n/YsN1C05V75Fuztt4irGhltlQxcG8F3gH/vqSy6VDdZb8lMU6+iyE2VKG
 ezsI7AMQkT6LrTGa2hXHHnnluaxHHSA32GPe4W1QTwMCMWMtRTwQHBBLoJ4mC0wk
 iujB9DVuh7ljmr7QSG9ZYV91eplpzJDUC54P6Qs/p7ouG4YzkIO6glt6BOgBmbp7
 YkrJtGpV6npjJmLckktcSd9rtnCzot6yGxeaIVfLPhhtf2KECSCckCyddwkakt0A
 wwVVBe8RNxXf2A==
 =xu7D
 -----END PGP SIGNATURE-----

Merge tag 'perf-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Thomas Gleixner:
 "A set of fixes and improvements for the perf subsystem:

  Kernel fixes:

   - Install cgroup events to the correct CPU context to prevent a
     potential list double add

   - Prevent an integer underflow in the perf mlock accounting

   - Add a missing prototype for arch_perf_update_userpage()

  Tooling:

   - Add a missing unlock in the error path of maps__insert() in perf
     maps.

   - Fix the build with the latest libbfd

   - Fix the perf parser so it does not delete parse event terms, which
     caused a regression for using perf with the ARM CoreSight as the
     sink configuration was missing due to the deletion.

   - Fix the double free in the perf CPU map merging test case

   - Add the missing ustring support for the perf probe command"

* tag 'perf-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf maps: Add missing unlock to maps__insert() error case
  perf probe: Add ustring support for perf probe command
  perf: Make perf able to build with latest libbfd
  perf test: Fix test case Merge cpu map
  perf parse: Copy string to perf_evsel_config_term
  perf parse: Refactor 'struct perf_evsel_config_term'
  kernel/events: Add a missing prototype for arch_perf_update_userpage()
  perf/cgroups: Install cgroup events to correct cpuctx
  perf/core: Fix mlock accounting in perf_mmap()
2020-02-09 12:04:09 -08:00
Linus Torvalds e310396bb8 Tracing updates:
- Added new "bootconfig".
    Looks for a file appended to initrd to add boot config options.
    This has been discussed thoroughly at Linux Plumbers.
    Very useful for adding kprobes at bootup.
    Only enabled if "bootconfig" is on the real kernel command line.
 
  - Created dynamic event creation.
    Merges common code between creating synthetic events and
      kprobe events.
 
  - Rename perf "ring_buffer" structure to "perf_buffer"
 
  - Rename ftrace "ring_buffer" structure to "trace_buffer"
    Had to rename existing "trace_buffer" to "array_buffer"
 
  - Allow trace_printk() to work withing (some) tracing code.
 
  - Sort of tracing configs to be a little better organized
 
  - Fixed bug where ftrace_graph hash was not being protected properly
 
  - Various other small fixes and clean ups
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXjtAURQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qshOAQDzopQmvAVrrI6oogghr8JQA30Z2yqT
 i+Ld7vPWL2MV9wEA1S+zLGDSYrj8f/vsCq6BxRYT1ApO+YtmY6LTXiUejwg=
 =WNds
 -----END PGP SIGNATURE-----

Merge tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - Added new "bootconfig".

   This looks for a file appended to initrd to add boot config options,
   and has been discussed thoroughly at Linux Plumbers.

   Very useful for adding kprobes at bootup.

   Only enabled if "bootconfig" is on the real kernel command line.

 - Created dynamic event creation.

   Merges common code between creating synthetic events and kprobe
   events.

 - Rename perf "ring_buffer" structure to "perf_buffer"

 - Rename ftrace "ring_buffer" structure to "trace_buffer"

   Had to rename existing "trace_buffer" to "array_buffer"

 - Allow trace_printk() to work withing (some) tracing code.

 - Sort of tracing configs to be a little better organized

 - Fixed bug where ftrace_graph hash was not being protected properly

 - Various other small fixes and clean ups

* tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (88 commits)
  bootconfig: Show the number of nodes on boot message
  tools/bootconfig: Show the number of bootconfig nodes
  bootconfig: Add more parse error messages
  bootconfig: Use bootconfig instead of boot config
  ftrace: Protect ftrace_graph_hash with ftrace_sync
  ftrace: Add comment to why rcu_dereference_sched() is open coded
  tracing: Annotate ftrace_graph_notrace_hash pointer with __rcu
  tracing: Annotate ftrace_graph_hash pointer with __rcu
  bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline
  tracing: Use seq_buf for building dynevent_cmd string
  tracing: Remove useless code in dynevent_arg_pair_add()
  tracing: Remove check_arg() callbacks from dynevent args
  tracing: Consolidate some synth_event_trace code
  tracing: Fix now invalid var_ref_vals assumption in trace action
  tracing: Change trace_boot to use synth_event interface
  tracing: Move tracing selftests to bottom of menu
  tracing: Move mmio tracer config up with the other tracers
  tracing: Move tracing test module configs together
  tracing: Move all function tracing configs together
  tracing: Documentation for in-kernel synthetic event API
  ...
2020-02-06 07:12:11 +00:00
Linus Torvalds 6aee4badd8 Merge branch 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull openat2 support from Al Viro:
 "This is the openat2() series from Aleksa Sarai.

  I'm afraid that the rest of namei stuff will have to wait - it got
  zero review the last time I'd posted #work.namei, and there had been a
  leak in the posted series I'd caught only last weekend. I was going to
  repost it on Monday, but the window opened and the odds of getting any
  review during that... Oh, well.

  Anyway, openat2 part should be ready; that _did_ get sane amount of
  review and public testing, so here it comes"

From Aleksa's description of the series:
 "For a very long time, extending openat(2) with new features has been
  incredibly frustrating. This stems from the fact that openat(2) is
  possibly the most famous counter-example to the mantra "don't silently
  accept garbage from userspace" -- it doesn't check whether unknown
  flags are present[1].

  This means that (generally) the addition of new flags to openat(2) has
  been fraught with backwards-compatibility issues (O_TMPFILE has to be
  defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
  kernels gave errors, since it's insecure to silently ignore the
  flag[2]). All new security-related flags therefore have a tough road
  to being added to openat(2).

  Furthermore, the need for some sort of control over VFS's path
  resolution (to avoid malicious paths resulting in inadvertent
  breakouts) has been a very long-standing desire of many userspace
  applications.

  This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
  (which was a variant of David Drysdale's O_BENEATH patchset[4] which
  was a spin-off of the Capsicum project[5]) with a few additions and
  changes made based on the previous discussion within [6] as well as
  others I felt were useful.

  In line with the conclusions of the original discussion of
  AT_NO_JUMPS, the flag has been split up into separate flags. However,
  instead of being an openat(2) flag it is provided through a new
  syscall openat2(2) which provides several other improvements to the
  openat(2) interface (see the patch description for more details). The
  following new LOOKUP_* flags are added:

  LOOKUP_NO_XDEV:

     Blocks all mountpoint crossings (upwards, downwards, or through
     absolute links). Absolute pathnames alone in openat(2) do not
     trigger this. Magic-link traversal which implies a vfsmount jump is
     also blocked (though magic-link jumps on the same vfsmount are
     permitted).

  LOOKUP_NO_MAGICLINKS:

     Blocks resolution through /proc/$pid/fd-style links. This is done
     by blocking the usage of nd_jump_link() during resolution in a
     filesystem. The term "magic-links" is used to match with the only
     reference to these links in Documentation/, but I'm happy to change
     the name.

     It should be noted that this is different to the scope of
     ~LOOKUP_FOLLOW in that it applies to all path components. However,
     you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
     will *not* fail (assuming that no parent component was a
     magic-link), and you will have an fd for the magic-link.

     In order to correctly detect magic-links, the introduction of a new
     LOOKUP_MAGICLINK_JUMPED state flag was required.

  LOOKUP_BENEATH:

     Disallows escapes to outside the starting dirfd's
     tree, using techniques such as ".." or absolute links. Absolute
     paths in openat(2) are also disallowed.

     Conceptually this flag is to ensure you "stay below" a certain
     point in the filesystem tree -- but this requires some additional
     to protect against various races that would allow escape using
     "..".

     Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
     can trivially beam you around the filesystem (breaking the
     protection). In future, there might be similar safety checks done
     as in LOOKUP_IN_ROOT, but that requires more discussion.

  In addition, two new flags are added that expand on the above ideas:

  LOOKUP_NO_SYMLINKS:

     Does what it says on the tin. No symlink resolution is allowed at
     all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
     can still be used with NOFOLLOW to open an fd for the symlink as
     long as no parent path had a symlink component.

  LOOKUP_IN_ROOT:

     This is an extension of LOOKUP_BENEATH that, rather than blocking
     attempts to move past the root, forces all such movements to be
     scoped to the starting point. This provides chroot(2)-like
     protection but without the cost of a chroot(2) for each filesystem
     operation, as well as being safe against race attacks that
     chroot(2) is not.

     If a race is detected (as with LOOKUP_BENEATH) then an error is
     generated, and similar to LOOKUP_BENEATH it is not permitted to
     cross magic-links with LOOKUP_IN_ROOT.

     The primary need for this is from container runtimes, which
     currently need to do symlink scoping in userspace[7] when opening
     paths in a potentially malicious container.

     There is a long list of CVEs that could have bene mitigated by
     having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
     CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
     few).

  In order to make all of the above more usable, I'm working on
  libpathrs[8] which is a C-friendly library for safe path resolution.
  It features a userspace-emulated backend if the kernel doesn't support
  openat2(2). Hopefully we can get userspace to switch to using it, and
  thus get openat2(2) support for free once it's ready.

  Future work would include implementing things like
  RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
  programs to be sure they don't hit DoSes though stale NFS handles)"

* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Documentation: path-lookup: include new LOOKUP flags
  selftests: add openat2(2) selftests
  open: introduce openat2(2) syscall
  namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
  namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
  namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
  namei: LOOKUP_NO_XDEV: block mountpoint crossing
  namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
  namei: LOOKUP_NO_SYMLINKS: block symlink resolution
  namei: allow set_root() to produce errors
  namei: allow nd_jump_link() to produce errors
  nsfs: clean-up ns_get_path() signature to return int
  namei: only return -ECHILD from follow_dotdot_rcu()
2020-01-29 11:20:24 -08:00
Song Liu 07c5972951 perf/cgroups: Install cgroup events to correct cpuctx
cgroup events are always installed in the cpuctx. However, when it is not
installed via IPI, list_update_cgroup_event() adds it to cpuctx of current
CPU, which triggers list corruption:

  [] list_add double add: new=ffff888ff7cf0db0, prev=ffff888ff7ce82f0, next=ffff888ff7cf0db0.

To reproduce this, we can simply run:

  # perf stat -e cs -a &
  # perf stat -e cs -G anycgroup

Fix this by installing it to cpuctx that contains event->ctx, and the
proper cgrp_cpuctx_list.

Fixes: db0503e4f6 ("perf/core: Optimize perf_install_in_event()")
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200122195027.2112449-1-songliubraving@fb.com
2020-01-28 21:20:19 +01:00
Song Liu 003461559e perf/core: Fix mlock accounting in perf_mmap()
Decreasing sysctl_perf_event_mlock between two consecutive perf_mmap()s of
a perf ring buffer may lead to an integer underflow in locked memory
accounting. This may lead to the undesired behaviors, such as failures in
BPF map creation.

Address this by adjusting the accounting logic to take into account the
possibility that the amount of already locked memory may exceed the
current limit.

Fixes: c4b7547974 ("perf/core: Make the mlock accounting simple again")
Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20200123181146.2238074-1-songliubraving@fb.com
2020-01-28 21:20:18 +01:00
Mark Rutland da9ec3d3dd perf: Correctly handle failed perf_get_aux_event()
Vince reports a worrying issue:

| so I was tracking down some odd behavior in the perf_fuzzer which turns
| out to be because perf_even_open() sometimes returns 0 (indicating a file
| descriptor of 0) even though as far as I can tell stdin is still open.

... and further the cause:

| error is triggered if aux_sample_size has non-zero value.
|
| seems to be this line in kernel/events/core.c:
|
| if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader))
|                goto err_locked;
|
| (note, err is never set)

This seems to be a thinko in commit:

  ab43762ef0 ("perf: Allow normal events to output AUX data")

... and we should probably return -EINVAL here, as this should only
happen when the new event is mis-configured or does not have a
compatible aux_event group leader.

Fixes: ab43762ef0 ("perf: Allow normal events to output AUX data")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
2020-01-17 11:32:44 +01:00
Steven Rostedt (VMware) 56de4e8f91 perf: Make struct ring_buffer less ambiguous
eBPF requires needing to know the size of the perf ring buffer structure.
But it unfortunately has the same name as the generic ring buffer used by
tracing and oprofile. To make it less ambiguous, rename the perf ring buffer
structure to "perf_buffer".

As other parts of the ring buffer code has "perf_" as the prefix, it only
makes sense to give the ring buffer the "perf_" prefix as well.

Link: https://lore.kernel.org/r/20191213153553.GE20583@krava
Acked-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13 13:19:38 -05:00
Sebastian Andrzej Siewior 9f0bff1180 perf/core: Add SRCU annotation for pmus list walk
Since commit
   28875945ba ("rcu: Add support for consolidated-RCU reader checking")

there is an additional check to ensure that a RCU related lock is held
while the RCU list is iterated.
This section holds the SRCU reader lock instead.

Add annotation to list_for_each_entry_rcu() that pmus_srcu must be
acquired during the list traversal.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lkml.kernel.org/r/20191119121429.zhcubzdhm672zasg@linutronix.de
2019-12-17 13:32:46 +01:00
Aleksa Sarai ce623f8987 nsfs: clean-up ns_get_path() signature to return int
ns_get_path() and ns_get_path_cb() only ever return either NULL or an
ERR_PTR. It is far more idiomatic to simply return an integer, and it
makes all of the callers of ns_get_path() more straightforward to read.

Fixes: e149ed2b80 ("take the targets of /proc/*/ns/* symlinks to separate fs")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-12-08 19:09:37 -05:00
Linus Torvalds 3f59dbcace Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main kernel side changes in this cycle were:

   - Various Intel-PT updates and optimizations (Alexander Shishkin)

   - Prohibit kprobes on Xen/KVM emulate prefixes (Masami Hiramatsu)

   - Add support for LSM and SELinux checks to control access to the
     perf syscall (Joel Fernandes)

   - Misc other changes, optimizations, fixes and cleanups - see the
     shortlog for details.

  There were numerous tooling changes as well - 254 non-merge commits.
  Here are the main changes - too many to list in detail:

   - Enhancements to core tooling infrastructure, perf.data, libperf,
     libtraceevent, event parsing, vendor events, Intel PT, callchains,
     BPF support and instruction decoding.

   - There were updates to the following tools:

        perf annotate
        perf diff
        perf inject
        perf kvm
        perf list
        perf maps
        perf parse
        perf probe
        perf record
        perf report
        perf script
        perf stat
        perf test
        perf trace

   - And a lot of other changes: please see the shortlog and Git log for
     more details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (279 commits)
  perf parse: Fix potential memory leak when handling tracepoint errors
  perf probe: Fix spelling mistake "addrees" -> "address"
  libtraceevent: Fix memory leakage in copy_filter_type
  libtraceevent: Fix header installation
  perf intel-bts: Does not support AUX area sampling
  perf intel-pt: Add support for decoding AUX area samples
  perf intel-pt: Add support for recording AUX area samples
  perf pmu: When using default config, record which bits of config were changed by the user
  perf auxtrace: Add support for queuing AUX area samples
  perf session: Add facility to peek at all events
  perf auxtrace: Add support for dumping AUX area samples
  perf inject: Cut AUX area samples
  perf record: Add aux-sample-size config term
  perf record: Add support for AUX area sampling
  perf auxtrace: Add support for AUX area sample recording
  perf auxtrace: Move perf_evsel__find_pmu()
  perf record: Add a function to test for kernel support for AUX area sampling
  perf tools: Add kernel AUX area sampling definitions
  perf/core: Make the mlock accounting simple again
  perf report: Jump to symbol source view from total cycles view
  ...
2019-11-26 15:04:47 -08:00
Linus Torvalds 386403a115 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
 "Another merge window, another pull full of stuff:

   1) Support alternative names for network devices, from Jiri Pirko.

   2) Introduce per-netns netdev notifiers, also from Jiri Pirko.

   3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
      Larsen.

   4) Allow compiling out the TLS TOE code, from Jakub Kicinski.

   5) Add several new tracepoints to the kTLS code, also from Jakub.

   6) Support set channels ethtool callback in ena driver, from Sameeh
      Jubran.

   7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
      SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.

   8) Add XDP support to mvneta driver, from Lorenzo Bianconi.

   9) Lots of netfilter hw offload fixes, cleanups and enhancements,
      from Pablo Neira Ayuso.

  10) PTP support for aquantia chips, from Egor Pomozov.

  11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
      Josh Hunt.

  12) Add smart nagle to tipc, from Jon Maloy.

  13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
      Duvvuru.

  14) Add a flow mask cache to OVS, from Tonghao Zhang.

  15) Add XDP support to ice driver, from Maciej Fijalkowski.

  16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.

  17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.

  18) Support it in stmmac driver too, from Jose Abreu.

  19) Support TIPC encryption and auth, from Tuong Lien.

  20) Introduce BPF trampolines, from Alexei Starovoitov.

  21) Make page_pool API more numa friendly, from Saeed Mahameed.

  22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.

  23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
  libbpf: Fix usage of u32 in userspace code
  mm: Implement no-MMU variant of vmalloc_user_node_flags
  slip: Fix use-after-free Read in slip_open
  net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
  macvlan: schedule bc_work even if error
  enetc: add support Credit Based Shaper(CBS) for hardware offload
  net: phy: add helpers phy_(un)lock_mdio_bus
  mdio_bus: don't use managed reset-controller
  ax88179_178a: add ethtool_op_get_ts_info()
  mlxsw: spectrum_router: Fix use of uninitialized adjacency index
  mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
  bpf: Simplify __bpf_arch_text_poke poke type handling
  bpf: Introduce BPF_TRACE_x helper for the tracing tests
  bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
  bpf, testing: Add various tail call test cases
  bpf, x86: Emit patchable direct jump as tail call
  bpf: Constant map key tracking for prog array pokes
  bpf: Add poke dependency tracking for prog array maps
  bpf: Add initial poke descriptor table for jit images
  bpf: Move owner type, jited info into array auxiliary data
  ...
2019-11-25 20:02:57 -08:00
Linus Torvalds 752272f16d ARM:
- Data abort report and injection
 - Steal time support
 - GICv4 performance improvements
 - vgic ITS emulation fixes
 - Simplify FWB handling
 - Enable halt polling counters
 - Make the emulated timer PREEMPT_RT compliant
 
 s390:
 - Small fixes and cleanups
 - selftest improvements
 - yield improvements
 
 PPC:
 - Add capability to tell userspace whether we can single-step the guest.
 - Improve the allocation of XIVE virtual processor IDs
 - Rewrite interrupt synthesis code to deliver interrupts in virtual
   mode when appropriate.
 - Minor cleanups and improvements.
 
 x86:
 - XSAVES support for AMD
 - more accurate report of nested guest TSC to the nested hypervisor
 - retpoline optimizations
 - support for nested 5-level page tables
 - PMU virtualization optimizations, and improved support for nested
   PMU virtualization
 - correct latching of INITs for nested virtualization
 - IOAPIC optimization
 - TSX_CTRL virtualization for more TAA happiness
 - improved allocation and flushing of SEV ASIDs
 - many bugfixes and cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2.0.22 (GNU/Linux)
 
 iQEcBAABAgAGBQJd27PMAAoJEL/70l94x66DspsH+gPc6YWtKJFJH58Zj8NrNh6y
 t0FwDFcvUa51+m4jaY4L5Y8+zqu1dZFnPPhFGqNWpxrjCEvE/glQJv3BiUX06Seh
 aYUHNymGoYCTJOHaaGhV+NlgQaDuZOCOkIsOLAPehyFd1KojwB+FRC0xmO6aROPw
 9yQgYrKuK1UUn5HwxBNrMS4+Xv+2iKv/9sTnq1G4W2qX2NZQg84LVPg1zIdkCh3D
 3GOvoCBEk3ivQqjmdE7rP/InPr0XvW0b6TFhchIk8J6jEIQFHsmOUefiTvTxsIHV
 OKAZwvyeYPrYHA/aDZpaBmY2aR0ydfKDUQcviNIJoF1vOktGs0hvl3VbsmG8QCg=
 =OSI1
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - data abort report and injection
   - steal time support
   - GICv4 performance improvements
   - vgic ITS emulation fixes
   - simplify FWB handling
   - enable halt polling counters
   - make the emulated timer PREEMPT_RT compliant

  s390:
   - small fixes and cleanups
   - selftest improvements
   - yield improvements

  PPC:
   - add capability to tell userspace whether we can single-step the
     guest
   - improve the allocation of XIVE virtual processor IDs
   - rewrite interrupt synthesis code to deliver interrupts in virtual
     mode when appropriate.
   - minor cleanups and improvements.

  x86:
   - XSAVES support for AMD
   - more accurate report of nested guest TSC to the nested hypervisor
   - retpoline optimizations
   - support for nested 5-level page tables
   - PMU virtualization optimizations, and improved support for nested
     PMU virtualization
   - correct latching of INITs for nested virtualization
   - IOAPIC optimization
   - TSX_CTRL virtualization for more TAA happiness
   - improved allocation and flushing of SEV ASIDs
   - many bugfixes and cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (127 commits)
  kvm: nVMX: Relax guest IA32_FEATURE_CONTROL constraints
  KVM: x86: Grab KVM's srcu lock when setting nested state
  KVM: x86: Open code shared_msr_update() in its only caller
  KVM: Fix jump label out_free_* in kvm_init()
  KVM: x86: Remove a spurious export of a static function
  KVM: x86: create mmu/ subdirectory
  KVM: nVMX: Remove unnecessary TLB flushes on L1<->L2 switches when L1 use apic-access-page
  KVM: x86: remove set but not used variable 'called'
  KVM: nVMX: Do not mark vmcs02->apic_access_page as dirty when unpinning
  KVM: vmx: use MSR_IA32_TSX_CTRL to hard-disable TSX on guest that lack it
  KVM: vmx: implement MSR_IA32_TSX_CTRL disable RTM functionality
  KVM: x86: implement MSR_IA32_TSX_CTRL effect on CPUID
  KVM: x86: do not modify masked bits of shared MSRs
  KVM: x86: fix presentation of TSX feature in ARCH_CAPABILITIES
  KVM: PPC: Book3S HV: XIVE: Fix potential page leak on error path
  KVM: PPC: Book3S HV: XIVE: Free previous EQ page when setting up a new one
  KVM: nVMX: Assume TLB entries of L1 and L2 are tagged differently if L0 use EPT
  KVM: x86: Unexport kvm_vcpu_reload_apic_access_page()
  KVM: nVMX: add CR4_LA57 bit to nested CR4_FIXED1
  KVM: nVMX: Use semi-colon instead of comma for exit-handlers initialization
  ...
2019-11-25 18:02:36 -08:00
Ingo Molnar c494cd6469 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-25 09:08:29 +01:00
Paolo Bonzini 46f4f0aabc Merge branch 'kvm-tsx-ctrl' into HEAD
Conflicts:
	arch/x86/kvm/vmx/vmx.c
2019-11-21 12:03:40 +01:00
Alexander Shishkin c4b7547974 perf/core: Make the mlock accounting simple again
Commit:

  d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")

does a lot of things to the mlock accounting arithmetics, while the only
thing that actually needed to happen is subtracting the part that is
charged to the mm from the part that is charged to the user, so that the
former isn't charged twice.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Cc: songliubraving@fb.com
Link: https://lkml.kernel.org/r/20191120170640.54123-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-21 07:37:50 +01:00
David S. Miller ee5a489fd9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2019-11-20

The following pull-request contains BPF updates for your *net-next* tree.

We've added 81 non-merge commits during the last 17 day(s) which contain
a total of 120 files changed, 4958 insertions(+), 1081 deletions(-).

There are 3 trivial conflicts, resolve it by always taking the chunk from
196e8ca74886c433:

<<<<<<< HEAD
=======
void *bpf_map_area_mmapable_alloc(u64 size, int numa_node);
>>>>>>> 196e8ca748

<<<<<<< HEAD
void *bpf_map_area_alloc(u64 size, int numa_node)
=======
static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
>>>>>>> 196e8ca748

<<<<<<< HEAD
        if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
=======
        /* kmalloc()'ed memory can't be mmap()'ed */
        if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
>>>>>>> 196e8ca748

The main changes are:

1) Addition of BPF trampoline which works as a bridge between kernel functions,
   BPF programs and other BPF programs along with two new use cases: i) fentry/fexit
   BPF programs for tracing with practically zero overhead to call into BPF (as
   opposed to k[ret]probes) and ii) attachment of the former to networking related
   programs to see input/output of networking programs (covering xdpdump use case),
   from Alexei Starovoitov.

2) BPF array map mmap support and use in libbpf for global data maps; also a big
   batch of libbpf improvements, among others, support for reading bitfields in a
   relocatable manner (via libbpf's CO-RE helper API), from Andrii Nakryiko.

3) Extend s390x JIT with usage of relative long jumps and loads in order to lift
   the current 64/512k size limits on JITed BPF programs there, from Ilya Leoshkevich.

4) Add BPF audit support and emit messages upon successful prog load and unload in
   order to have a timeline of events, from Daniel Borkmann and Jiri Olsa.

5) Extension to libbpf and xdpsock sample programs to demo the shared umem mode
   (XDP_SHARED_UMEM) as well as RX-only and TX-only sockets, from Magnus Karlsson.

6) Several follow-up bug fixes for libbpf's auto-pinning code and a new API
   call named bpf_get_link_xdp_info() for retrieving the full set of prog
   IDs attached to XDP, from Toke Høiland-Jørgensen.

7) Add BTF support for array of int, array of struct and multidimensional arrays
   and enable it for skb->cb[] access in kfree_skb test, from Martin KaFai Lau.

8) Fix AF_XDP by using the correct number of channels from ethtool, from Luigi Rizzo.

9) Two fixes for BPF selftest to get rid of a hang in test_tc_tunnel and to avoid
   xdping to be run as standalone, from Jiri Benc.

10) Various BPF selftest fixes when run with latest LLVM trunk, from Yonghong Song.

11) Fix a memory leak in BPF fentry test run data, from Colin Ian King.

12) Various smaller misc cleanups and improvements mostly all over BPF selftests and
    samples, from Daniel T. Lee, Andre Guedes, Anders Roxell, Mao Wenan, Yue Haibing.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-20 18:11:23 -08:00
Alexander Shishkin 36b3db03b4 perf/core: Fix the mlock accounting, again
Commit:

  5e6c3c7b1e ("perf/aux: Fix tracking of auxiliary trace buffer allocation")

tried to guess the correct combination of arithmetic operations that would
undo the AUX buffer's mlock accounting, and failed, leaking the bottom part
when an allocation needs to be charged partially to both user->locked_vm
and mm->pinned_vm, eventually leaving the user with no locked bonus:

  $ perf record -e intel_pt//u -m1,128 uname
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.061 MB perf.data ]

  $ perf record -e intel_pt//u -m1,128 uname
  Permission error mapping pages.
  Consider increasing /proc/sys/kernel/perf_event_mlock_kb,
  or try again with a smaller value of -m/--mmap_pages.
  (current value: 1,128)

Fix this by subtracting both locked and pinned counts when AUX buffer is
unmapped.

Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-18 16:27:37 +01:00
Andrii Nakryiko 85192dbf4d bpf: Convert bpf_prog refcnt to atomic64_t
Similarly to bpf_map's refcnt/usercnt, convert bpf_prog's refcnt to atomic64
and remove artificial 32k limit. This allows to make bpf_prog's refcounting
non-failing, simplifying logic of users of bpf_prog_add/bpf_prog_inc.

Validated compilation by running allyesconfig kernel build.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-3-andriin@fb.com
2019-11-18 11:41:59 +01:00
Like Xu 52ba4b0b99 perf/core: Provide a kernel-internal interface to pause perf_event
Exporting perf_event_pause() as an external accessor for kernel users (such
as KVM) who may do both disable perf_event and read count with just one
time to hold perf_event_ctx_lock. Also the value could be reset optionally.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-15 11:44:07 +01:00
Like Xu 3ca270fc9e perf/core: Provide a kernel-internal interface to recalibrate event period
Currently, perf_event_period() is used by user tools via ioctl. Based on
naming convention, exporting perf_event_period() for kernel users (such
as KVM) who may recalibrate the event period for their assigned counter
according to their requirements.

The perf_event_period() is an external accessor, just like the
perf_event_{en,dis}able() and should thus use perf_event_ctx_lock().

Suggested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-11-15 11:44:06 +01:00
Alexander Shishkin a4faf00d99 perf/aux: Allow using AUX data in perf samples
AUX data can be used to annotate perf events such as performance counters
or tracepoints/breakpoints by including it in sample records when
PERF_SAMPLE_AUX flag is set. Such samples would be instrumental in debugging
and profiling by providing, for example, a history of instruction flow
leading up to the event's overflow.

The implementation makes use of grouping an AUX event with all the events
that wish to take samples of the AUX data, such that the former is the
group leader. The samplees should also specify the desired size of the AUX
sample via attr.aux_sample_size.

AUX capable PMUs need to explicitly add support for sampling, because it
relies on a new callback to take a snapshot of the buffer without touching
the event states.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: adrian.hunter@intel.com
Cc: mathieu.poirier@linaro.org
Link: https://lkml.kernel.org/r/20191025140835.53665-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 11:06:14 +01:00
Qian Cai deb0c3c29d perf/core: Fix unlock balance in perf_init_event()
Commit:

  66d258c5b0 ("perf/core: Optimize perf_init_event()")

introduced an unlock imbalance in perf_init_event() where it calls
"goto again" and then only repeat rcu_read_unlock().

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 66d258c5b0 ("perf/core: Optimize perf_init_event()")
Link: https://lkml.kernel.org/r/20191106052935.8352-1-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 11:06:13 +01:00
Ingo Molnar fed4c9c681 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 11:04:43 +01:00
Ben Dooks (Codethink) d00dbd2981 perf/core: Fix missing static inline on perf_cgroup_switch()
It looks like a "static inline" has been missed in front
of the empty definition of perf_cgroup_switch() under
certain configurations.

Fixes the following sparse warning:

  kernel/events/core.c:1035:1: warning: symbol 'perf_cgroup_switch' was not declared. Should it be static?

Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191106132527.19977-1-ben.dooks@codethink.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:44 +01:00
Alexander Shishkin 697d877849 perf/core: Consistently fail fork on allocation failures
Commit:

  313ccb9615 ("perf: Allocate context task_ctx_data for child event")

makes the inherit path skip over the current event in case of task_ctx_data
allocation failure. This, however, is inconsistent with allocation failures
in perf_event_alloc(), which would abort the fork.

Correct this by returning an error code on task_ctx_data allocation
failure and failing the fork in that case.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191105075702.60319-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:43 +01:00
Alexander Shishkin dce5affb94 perf/aux: Disallow aux_output for kernel events
Commit

  ab43762ef0 ("perf: Allow normal events to output AUX data")

added 'aux_output' bit to the attribute structure, which relies on AUX
events and grouping, neither of which is supported for the kernel events.
This notwithstanding, attempts have been made to use it in the kernel
code, suggesting the necessity of an explicit hard -EINVAL.

Fix this by rejecting attributes with aux_output set for kernel events.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191030134731.5437-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:42 +01:00
Alexander Shishkin f25d8ba9e1 perf/core: Reattach a misplaced comment
A comment is in a wrong place in perf_event_create_kernel_counter().
Fix that.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191030134731.5437-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:41 +01:00
Alexander Shishkin 00496fe5e0 perf/aux: Fix the aux_output group inheritance fix
Commit

  f733c6b508 ("perf/core: Fix inheritance of aux_output groups")

adds a NULL pointer dereference in case inherit_group() races with
perf_release(), which causes the below crash:

 > BUG: kernel NULL pointer dereference, address: 000000000000010b
 > #PF: supervisor read access in kernel mode
 > #PF: error_code(0x0000) - not-present page
 > PGD 3b203b067 P4D 3b203b067 PUD 3b2040067 PMD 0
 > Oops: 0000 [#1] SMP KASAN
 > CPU: 0 PID: 315 Comm: exclusive-group Tainted: G B 5.4.0-rc3-00181-g72e1839403cb-dirty #878
 > RIP: 0010:perf_get_aux_event+0x86/0x270
 > Call Trace:
 >  ? __perf_read_group_add+0x3b0/0x3b0
 >  ? __kasan_check_write+0x14/0x20
 >  ? __perf_event_init_context+0x154/0x170
 >  inherit_task_group.isra.0.part.0+0x14b/0x170
 >  perf_event_init_task+0x296/0x4b0

Fix this by skipping over events that are getting closed, in the
inheritance path.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: f733c6b508 ("perf/core: Fix inheritance of aux_output groups")
Link: https://lkml.kernel.org/r/20191101151248.47327-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:40 +01:00
Peter Zijlstra 09f4e8f05d perf/core: Disallow uncore-cgroup events
While discussing uncore event scheduling, I noticed we do not in fact
seem to dis-allow making uncore-cgroup events. Such events make no
sense what so ever because the cgroup is a CPU local state where
uncore counts across a number of CPUs.

Disallow them.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-11-13 08:16:39 +01:00
Liang, Kan d44f821b0e perf/core: Optimize perf_init_event() for TYPE_SOFTWARE
Andi reported that he was hitting the linear search in
perf_init_event() a lot. Now that all !TYPE_SOFTWARE events should hit
the IDR, make sure the TYPE_SOFTWARE events are at the head of the
list such that we'll quickly find the right PMU (provided a valid
event was given).

Signed-off-by: Liang, Kan <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:53:28 +01:00
Peter Zijlstra 66d258c5b0 perf/core: Optimize perf_init_event()
Andi reported that he was hitting the linear search in
perf_init_event() a lot. Make more agressive use of the IDR lookup to
avoid hitting the linear search.

With exception of PERF_TYPE_SOFTWARE (which relies on a hideous hack),
we can put everything in the IDR. On top of that, we can alias
TYPE_HARDWARE and TYPE_HW_CACHE to TYPE_RAW on the lookup side.

This greatly reduces the chances of hitting the linear search.

Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:51:02 +01:00
Peter Zijlstra db0503e4f6 perf/core: Optimize perf_install_in_event()
Andi reported that when creating a lot of events, a lot of time is
spent in IPIs and asked if it would be possible to elide some of that.

Now when, as for example the perf-tool always does, events are created
disabled, then these events will not need to be scheduled when added
to the context (they're still disable) and therefore the IPI is not
required -- except for the very first event, that will need to set
ctx->is_active.

( It might be possible to set ctx->is_active remotely for cpu_ctx, but
  we really need the IPI for task_ctx, so lets not make that
  distinction. )

Also use __perf_effective_state() since group events depend on the
state of the leader, if the leader is OFF, the whole group is OFF.

So when sibling events are created enabled (XXX check tool) then we
only need a single IPI to create and enable the whole group (+ that
initial IPI to initialize the context).

Suggested-by: Andi Kleen <andi@firstfloor.org>
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:51:02 +01:00
Alexey Budankov c2b98a8661 perf/x86: Synchronize PMU task contexts on optimized context switches
Install Intel specific PMU task context synchronization adapter and
extend optimized context switch path with PMU specific task context
synchronization to fix LBR callstack virtualization on context switches.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/9c6445a9-bdba-ef03-3859-f1f91198f27a@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:51:01 +01:00
Ingo Molnar 65133033ee Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 12:38:26 +01:00
Alexander Shishkin 8c7e975667 perf/core: Start rejecting the syscall with attr.__reserved_2 set
Commit:

  1a59413124 ("perf: Add wakeup watermark control to the AUX area")

added attr.__reserved_2 padding, but forgot to add an ABI check to reject
attributes with this field set. Fix that.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: adrian.hunter@intel.com
Cc: mathieu.poirier@linaro.org
Link: https://lkml.kernel.org/r/20191025121636.75182-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-28 11:01:59 +01:00
Alexander Shishkin f3a519e4ad perf/aux: Fix AUX output stopping
Commit:

  8a58ddae23 ("perf/core: Fix exclusive events' grouping")

allows CAP_EXCLUSIVE events to be grouped with other events. Since all
of those also happen to be AUX events (which is not the case the other
way around, because arch/s390), this changes the rules for stopping the
output: the AUX event may not be on its PMU's context any more, if it's
grouped with a HW event, in which case it will be on that HW event's
context instead. If that's the case, munmap() of the AUX buffer can't
find and stop the AUX event, potentially leaving the last reference with
the atomic context, which will then end up freeing the AUX buffer. This
will then trip warnings:

Fix this by using the context's PMU context when looking for events
to stop, instead of the event's PMU context.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191022073940.61814-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-22 14:39:37 +02:00
Ingo Molnar aa7a7b7297 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-22 01:15:32 +02:00
Thomas Richter 5e6c3c7b1e perf/aux: Fix tracking of auxiliary trace buffer allocation
The following commit from the v5.4 merge window:

  d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")

... breaks auxiliary trace buffer tracking.

If I run command 'perf record -e rbd000' to record samples and saving
them in the **auxiliary** trace buffer then the value of 'locked_vm' becomes
negative after all trace buffers have been allocated and released:

During allocation the values increase:

  [52.250027] perf_mmap user->locked_vm:0x87 pinned_vm:0x0 ret:0
  [52.250115] perf_mmap user->locked_vm:0x107 pinned_vm:0x0 ret:0
  [52.250251] perf_mmap user->locked_vm:0x188 pinned_vm:0x0 ret:0
  [52.250326] perf_mmap user->locked_vm:0x208 pinned_vm:0x0 ret:0
  [52.250441] perf_mmap user->locked_vm:0x289 pinned_vm:0x0 ret:0
  [52.250498] perf_mmap user->locked_vm:0x309 pinned_vm:0x0 ret:0
  [52.250613] perf_mmap user->locked_vm:0x38a pinned_vm:0x0 ret:0
  [52.250715] perf_mmap user->locked_vm:0x408 pinned_vm:0x2 ret:0
  [52.250834] perf_mmap user->locked_vm:0x408 pinned_vm:0x83 ret:0
  [52.250915] perf_mmap user->locked_vm:0x408 pinned_vm:0x103 ret:0
  [52.251061] perf_mmap user->locked_vm:0x408 pinned_vm:0x184 ret:0
  [52.251146] perf_mmap user->locked_vm:0x408 pinned_vm:0x204 ret:0
  [52.251299] perf_mmap user->locked_vm:0x408 pinned_vm:0x285 ret:0
  [52.251383] perf_mmap user->locked_vm:0x408 pinned_vm:0x305 ret:0
  [52.251544] perf_mmap user->locked_vm:0x408 pinned_vm:0x386 ret:0
  [52.251634] perf_mmap user->locked_vm:0x408 pinned_vm:0x406 ret:0
  [52.253018] perf_mmap user->locked_vm:0x408 pinned_vm:0x487 ret:0
  [52.253197] perf_mmap user->locked_vm:0x408 pinned_vm:0x508 ret:0
  [52.253374] perf_mmap user->locked_vm:0x408 pinned_vm:0x589 ret:0
  [52.253550] perf_mmap user->locked_vm:0x408 pinned_vm:0x60a ret:0
  [52.253726] perf_mmap user->locked_vm:0x408 pinned_vm:0x68b ret:0
  [52.253903] perf_mmap user->locked_vm:0x408 pinned_vm:0x70c ret:0
  [52.254084] perf_mmap user->locked_vm:0x408 pinned_vm:0x78d ret:0
  [52.254263] perf_mmap user->locked_vm:0x408 pinned_vm:0x80e ret:0

The value of user->locked_vm increases to a limit then the memory
is tracked by pinned_vm.

During deallocation the size is subtracted from pinned_vm until
it hits a limit. Then a larger value is subtracted from locked_vm
leading to a large number (because of type unsigned):

  [64.267797] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x78d
  [64.267826] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x70c
  [64.267848] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x68b
  [64.267869] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x60a
  [64.267891] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x589
  [64.267911] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x508
  [64.267933] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x487
  [64.267952] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x406
  [64.268883] perf_mmap_close mmap_user->locked_vm:0x307 pinned_vm:0x406
  [64.269117] perf_mmap_close mmap_user->locked_vm:0x206 pinned_vm:0x406
  [64.269433] perf_mmap_close mmap_user->locked_vm:0x105 pinned_vm:0x406
  [64.269536] perf_mmap_close mmap_user->locked_vm:0x4 pinned_vm:0x404
  [64.269797] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff84 pinned_vm:0x303
  [64.270105] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff04 pinned_vm:0x202
  [64.270374] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe84 pinned_vm:0x101
  [64.270628] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe04 pinned_vm:0x0

This value sticks for the user until system is rebooted, causing
follow-on system calls using locked_vm resource limit to fail.

Note: There is no issue using the normal trace buffer.

In fact the issue is in perf_mmap_close(). During allocation auxiliary
trace buffer memory is either traced as 'extra' and added to 'pinned_vm'
or trace as 'user_extra' and added to 'locked_vm'. This applies for
normal trace buffers and auxiliary trace buffer.

However in function perf_mmap_close() all auxiliary trace buffer is
subtraced from 'locked_vm' and never from 'pinned_vm'. This breaks the
ballance.

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: gor@linux.ibm.com
Cc: hechaol@fb.com
Cc: heiko.carstens@de.ibm.com
Cc: linux-perf-users@vger.kernel.org
Cc: songliubraving@fb.com
Fixes: d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
Link: https://lkml.kernel.org/r/20191021083354.67868-1-tmricht@linux.ibm.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-21 11:31:24 +02:00
Joel Fernandes (Google) da97e18458 perf_event: Add support for LSM and SELinux checks
In current mainline, the degree of access to perf_event_open(2) system
call depends on the perf_event_paranoid sysctl.  This has a number of
limitations:

1. The sysctl is only a single value. Many types of accesses are controlled
   based on the single value thus making the control very limited and
   coarse grained.
2. The sysctl is global, so if the sysctl is changed, then that means
   all processes get access to perf_event_open(2) opening the door to
   security issues.

This patch adds LSM and SELinux access checking which will be used in
Android to access perf_event_open(2) for the purposes of attaching BPF
programs to tracepoints, perf profiling and other operations from
userspace. These operations are intended for production systems.

5 new LSM hooks are added:
1. perf_event_open: This controls access during the perf_event_open(2)
   syscall itself. The hook is called from all the places that the
   perf_event_paranoid sysctl is checked to keep it consistent with the
   systctl. The hook gets passed a 'type' argument which controls CPU,
   kernel and tracepoint accesses (in this context, CPU, kernel and
   tracepoint have the same semantics as the perf_event_paranoid sysctl).
   Additionally, I added an 'open' type which is similar to
   perf_event_paranoid sysctl == 3 patch carried in Android and several other
   distros but was rejected in mainline [1] in 2016.

2. perf_event_alloc: This allocates a new security object for the event
   which stores the current SID within the event. It will be useful when
   the perf event's FD is passed through IPC to another process which may
   try to read the FD. Appropriate security checks will limit access.

3. perf_event_free: Called when the event is closed.

4. perf_event_read: Called from the read(2) and mmap(2) syscalls for the event.

5. perf_event_write: Called from the ioctl(2) syscalls for the event.

[1] https://lwn.net/Articles/696240/

Since Peter had suggest LSM hooks in 2016 [1], I am adding his
Suggested-by tag below.

To use this patch, we set the perf_event_paranoid sysctl to -1 and then
apply selinux checking as appropriate (default deny everything, and then
add policy rules to give access to domains that need it). In the future
we can remove the perf_event_paranoid sysctl altogether.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Co-developed-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: James Morris <jmorris@namei.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: rostedt@goodmis.org
Cc: Yonghong Song <yhs@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: jeffv@google.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: primiano@google.com
Cc: Song Liu <songliubraving@fb.com>
Cc: rsavitski@google.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Matthew Garrett <matthewgarrett@google.com>
Link: https://lkml.kernel.org/r/20191014170308.70668-1-joel@joelfernandes.org
2019-10-17 21:31:55 +02:00
Song Liu 7fa343b7fd perf/core: Fix corner case in perf_rotate_context()
In perf_rotate_context(), when the first cpu flexible event fail to
schedule, cpu_rotate is 1, while cpu_event is NULL. Since cpu_event is
NULL, perf_rotate_context will _NOT_ call cpu_ctx_sched_out(), thus
cpuctx->ctx.is_active will have EVENT_FLEXIBLE set. Then, the next
perf_event_sched_in() will skip all cpu flexible events because of the
EVENT_FLEXIBLE bit.

In the next call of perf_rotate_context(), cpu_rotate stays 1, and
cpu_event stays NULL, so this process repeats. The end result is, flexible
events on this cpu will not be scheduled (until another event being added
to the cpuctx).

Here is an easy repro of this issue. On Intel CPUs, where ref-cycles
could only use one counter, run one pinned event for ref-cycles, one
flexible event for ref-cycles, and one flexible event for cycles. The
flexible ref-cycles is never scheduled, which is expected. However,
because of this issue, the cycles event is never scheduled either.

 $ perf stat -e ref-cycles:D,ref-cycles,cycles -C 5 -I 1000

           time             counts unit events
    1.000152973         15,412,480      ref-cycles:D
    1.000152973      <not counted>      ref-cycles     (0.00%)
    1.000152973      <not counted>      cycles         (0.00%)
    2.000486957         18,263,120      ref-cycles:D
    2.000486957      <not counted>      ref-cycles     (0.00%)
    2.000486957      <not counted>      cycles         (0.00%)

To fix this, when the flexible_active list is empty, try rotate the
first event in the flexible_groups. Also, rename ctx_first_active() to
ctx_event_to_rotate(), which is more accurate.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8d5bce0c37 ("perf/core: Optimize perf_rotate_context() event scheduling")
Link: https://lkml.kernel.org/r/20191008165949.920548-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:44:13 +02:00
Song Liu d44248a413 perf/core: Rework memory accounting in perf_mmap()
perf_mmap() always increases user->locked_vm. As a result, "extra" could
grow bigger than "user_extra", which doesn't make sense. Here is an
example case:

(Note: Assume "user_lock_limit" is very small.)

  | # of perf_mmap calls |vma->vm_mm->pinned_vm|user->locked_vm|
  | 0                    | 0                   | 0             |
  | 1                    | user_extra          | user_extra    |
  | 2                    | 3 * user_extra      | 2 * user_extra|
  | 3                    | 6 * user_extra      | 3 * user_extra|
  | 4                    | 10 * user_extra     | 4 * user_extra|

Fix this by maintaining proper user_extra and extra.

Reviewed-By: Hechao Li <hechaol@fb.com>
Reported-by: Hechao Li <hechaol@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Jie Meng <jmeng@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190904214618.3795672-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:44:12 +02:00
Alexander Shishkin f733c6b508 perf/core: Fix inheritance of aux_output groups
Commit:

  ab43762ef0 ("perf: Allow normal events to output AUX data")

forgets to configure aux_output relation in the inherited groups, which
results in child PEBS events forever failing to schedule.

Fix this by setting up the AUX output link in the inheritance path.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191004125729.32397-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-07 16:50:42 +02:00
Aleksa Sarai c2ba8f41ad perf_event_open: switch to copy_struct_from_user()
Switch perf_event_open() syscall from it's own copying
struct perf_event_attr from userspace to the new dedicated
copy_struct_from_user() helper.

The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-5-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2019-10-01 15:45:22 +02:00
Linus Torvalds aefcf2f4b5 Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull kernel lockdown mode from James Morris:
 "This is the latest iteration of the kernel lockdown patchset, from
  Matthew Garrett, David Howells and others.

  From the original description:

    This patchset introduces an optional kernel lockdown feature,
    intended to strengthen the boundary between UID 0 and the kernel.
    When enabled, various pieces of kernel functionality are restricted.
    Applications that rely on low-level access to either hardware or the
    kernel may cease working as a result - therefore this should not be
    enabled without appropriate evaluation beforehand.

    The majority of mainstream distributions have been carrying variants
    of this patchset for many years now, so there's value in providing a
    doesn't meet every distribution requirement, but gets us much closer
    to not requiring external patches.

  There are two major changes since this was last proposed for mainline:

   - Separating lockdown from EFI secure boot. Background discussion is
     covered here: https://lwn.net/Articles/751061/

   -  Implementation as an LSM, with a default stackable lockdown LSM
      module. This allows the lockdown feature to be policy-driven,
      rather than encoding an implicit policy within the mechanism.

  The new locked_down LSM hook is provided to allow LSMs to make a
  policy decision around whether kernel functionality that would allow
  tampering with or examining the runtime state of the kernel should be
  permitted.

  The included lockdown LSM provides an implementation with a simple
  policy intended for general purpose use. This policy provides a coarse
  level of granularity, controllable via the kernel command line:

    lockdown={integrity|confidentiality}

  Enable the kernel lockdown feature. If set to integrity, kernel features
  that allow userland to modify the running kernel are disabled. If set to
  confidentiality, kernel features that allow userland to extract
  confidential information from the kernel are also disabled.

  This may also be controlled via /sys/kernel/security/lockdown and
  overriden by kernel configuration.

  New or existing LSMs may implement finer-grained controls of the
  lockdown features. Refer to the lockdown_reason documentation in
  include/linux/security.h for details.

  The lockdown feature has had signficant design feedback and review
  across many subsystems. This code has been in linux-next for some
  weeks, with a few fixes applied along the way.

  Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
  when kernel lockdown is in confidentiality mode") is missing a
  Signed-off-by from its author. Matthew responded that he is providing
  this under category (c) of the DCO"

* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
  kexec: Fix file verification on S390
  security: constify some arrays in lockdown LSM
  lockdown: Print current->comm in restriction messages
  efi: Restrict efivar_ssdt_load when the kernel is locked down
  tracefs: Restrict tracefs when the kernel is locked down
  debugfs: Restrict debugfs when the kernel is locked down
  kexec: Allow kexec_file() with appropriate IMA policy when locked down
  lockdown: Lock down perf when in confidentiality mode
  bpf: Restrict bpf when kernel lockdown is in confidentiality mode
  lockdown: Lock down tracing and perf kprobes when in confidentiality mode
  lockdown: Lock down /proc/kcore
  x86/mmiotrace: Lock down the testmmiotrace module
  lockdown: Lock down module params that specify hardware parameters (eg. ioport)
  lockdown: Lock down TIOCSSERIAL
  lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
  acpi: Disable ACPI table override if the kernel is locked down
  acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
  ACPI: Limit access to custom_method when the kernel is locked down
  x86/msr: Restrict MSR access when the kernel is locked down
  x86: Lock down IO port access when the kernel is locked down
  ...
2019-09-28 08:14:15 -07:00
Roy Ben Shlomo 9f014e3a66 perf/core: Fix several typos in comments
Fix typos in a few functions' documentation comments.

Signed-off-by: Roy Ben Shlomo <royb@sentinelone.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: royb@sentinelone.com
Link: http://lore.kernel.org/lkml/20190920171254.31373-1-royb@sentinelone.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-09-20 16:05:20 -03:00
Linus Torvalds 7f2444d38f Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core timer updates from Thomas Gleixner:
 "Timers and timekeeping updates:

   - A large overhaul of the posix CPU timer code which is a preparation
     for moving the CPU timer expiry out into task work so it can be
     properly accounted on the task/process.

     An update to the bogus permission checks will come later during the
     merge window as feedback was not complete before heading of for
     travel.

   - Switch the timerqueue code to use cached rbtrees and get rid of the
     homebrewn caching of the leftmost node.

   - Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
     single function

   - Implement the separation of hrtimers to be forced to expire in hard
     interrupt context even when PREEMPT_RT is enabled and mark the
     affected timers accordingly.

   - Implement a mechanism for hrtimers and the timer wheel to protect
     RT against priority inversion and live lock issues when a (hr)timer
     which should be canceled is currently executing the callback.
     Instead of infinitely spinning, the task which tries to cancel the
     timer blocks on a per cpu base expiry lock which is held and
     released by the (hr)timer expiry code.

   - Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
     resulting in faster access to timekeeping functions.

   - Updates to various clocksource/clockevent drivers and their device
     tree bindings.

   - The usual small improvements all over the place"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
  posix-cpu-timers: Fix permission check regression
  posix-cpu-timers: Always clear head pointer on dequeue
  hrtimer: Add a missing bracket and hide `migration_base' on !SMP
  posix-cpu-timers: Make expiry_active check actually work correctly
  posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
  tick: Mark sched_timer to expire in hard interrupt context
  hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
  x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
  posix-cpu-timers: Utilize timerqueue for storage
  posix-cpu-timers: Move state tracking to struct posix_cputimers
  posix-cpu-timers: Deduplicate rlimit handling
  posix-cpu-timers: Remove pointless comparisons
  posix-cpu-timers: Get rid of 64bit divisions
  posix-cpu-timers: Consolidate timer expiry further
  posix-cpu-timers: Get rid of zero checks
  rlimit: Rewrite non-sensical RLIMIT_CPU comment
  posix-cpu-timers: Respect INFINITY for hard RTTIME limit
  posix-cpu-timers: Switch thread group sampling to array
  posix-cpu-timers: Restructure expiry array
  posix-cpu-timers: Remove cputime_expires
  ...
2019-09-17 12:35:15 -07:00
Linus Torvalds 7e67a85999 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
   Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
   Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.

   As perf and the scheduler is getting bigger and more complex,
   document the status quo of current responsibilities and interests,
   and spread the review pain^H^H^H^H fun via an increase in the Cc:
   linecount generated by scripts/get_maintainer.pl. :-)

 - Add another series of patches that brings the -rt (PREEMPT_RT) tree
   closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
   into a new CONFIG_PREEMPTION category that will allow the eventual
   introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
   to go though.

 - Extend the CPU cgroup controller with uclamp.min and uclamp.max to
   allow the finer shaping of CPU bandwidth usage.

 - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).

 - Improve the behavior of high CPU count, high thread count
   applications running under cpu.cfs_quota_us constraints.

 - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.

 - Improve CPU isolation housekeeping CPU allocation NUMA locality.

 - Fix deadline scheduler bandwidth calculations and logic when cpusets
   rebuilds the topology, or when it gets deadline-throttled while it's
   being offlined.

 - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
   setscheduler() system calls without creating global serialization.
   Add new synchronization between cpuset topology-changing events and
   the deadline acceptance tests in setscheduler(), which were broken
   before.

 - Rework the active_mm state machine to be less confusing and more
   optimal.

 - Rework (simplify) the pick_next_task() slowpath.

 - Improve load-balancing on AMD EPYC systems.

 - ... and misc cleanups, smaller fixes and improvements - please see
   the Git log for more details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
  sched/psi: Correct overly pessimistic size calculation
  sched/fair: Speed-up energy-aware wake-ups
  sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
  sched/uclamp: Update CPU's refcount on TG's clamp changes
  sched/uclamp: Use TG's clamps to restrict TASK's clamps
  sched/uclamp: Propagate system defaults to the root group
  sched/uclamp: Propagate parent clamps
  sched/uclamp: Extend CPU's cgroup controller
  sched/topology: Improve load balancing on AMD EPYC systems
  arch, ia64: Make NUMA select SMP
  sched, perf: MAINTAINERS update, add submaintainers and reviewers
  sched/fair: Use rq_lock/unlock in online_fair_sched_group
  cpufreq: schedutil: fix equation in comment
  sched: Rework pick_next_task() slow-path
  sched: Allow put_prev_task() to drop rq->lock
  sched/fair: Expose newidle_balance()
  sched: Add task_struct pointer to sched_class::set_curr_task
  sched: Rework CPU hotplug task selection
  sched/{rt,deadline}: Fix set_next_task vs pick_next_task
  sched: Fix kerneldoc comment for ia64_set_curr_task
  ...
2019-09-16 17:25:49 -07:00
Ingo Molnar 563c4f85f9 Merge branch 'sched/rt' into sched/core, to pick up -rt changes
Pick up the first couple of patches working towards PREEMPT_RT.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-09-16 14:05:04 +02:00
Alexander Shishkin ab43762ef0 perf: Allow normal events to output AUX data
In some cases, ordinary (non-AUX) events can generate data for AUX events.
For example, PEBS events can come out as records in the Intel PT stream
instead of their usual DS records, if configured to do so.

One requirement for such events is to consistently schedule together, to
ensure that the data from the "AUX output" events isn't lost while their
corresponding AUX event is not scheduled. We use grouping to provide this
guarantee: an "AUX output" event can be added to a group where an AUX event
is a group leader, and provided that the former supports writing to the
latter.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: kan.liang@linux.intel.com
Link: https://lkml.kernel.org/r/20190806084606.4021-2-alexander.shishkin@linux.intel.com
2019-08-28 11:29:38 +02:00
David Howells b0c8fdc7fd lockdown: Lock down perf when in confidentiality mode
Disallow the use of certain perf facilities that might allow userspace to
access kernel data.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
2019-08-19 21:54:16 -07:00
Sebastian Andrzej Siewior 30f9028b6c perf/core: Mark hrtimers to expire in hard interrupt context
To guarantee that the multiplexing mechanism and the hrtimer driven events
work on PREEMPT_RT enabled kernels it's required that the related hrtimers
expire in hard interrupt context. Mark them so PREEMPT_RT kernels wont
defer them to soft interrupt context.

No functional change.

[ tglx: Split out of larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.169509224@linutronix.de
2019-08-01 20:51:20 +02:00
Matthew Wilcox (Oracle) 7b3c92b85a sched/core: Convert get_task_struct() to return the task
Returning the pointer that was passed in allows us to write
slightly more idiomatic code.  Convert a few users.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190704221323.24290-1-willy@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:51:54 +02:00
Leonard Crestez 4ce54af8b3 perf/core: Fix creating kernel counters for PMUs that override event->cpu
Some hardware PMU drivers will override perf_event.cpu inside their
event_init callback. This causes a lockdep splat when initialized through
the kernel API:

 WARNING: CPU: 0 PID: 250 at kernel/events/core.c:2917 ctx_sched_out+0x78/0x208
 pc : ctx_sched_out+0x78/0x208
 Call trace:
  ctx_sched_out+0x78/0x208
  __perf_install_in_context+0x160/0x248
  remote_function+0x58/0x68
  generic_exec_single+0x100/0x180
  smp_call_function_single+0x174/0x1b8
  perf_install_in_context+0x178/0x188
  perf_event_create_kernel_counter+0x118/0x160

Fix this by calling perf_install_in_context with event->cpu, just like
perf_event_open

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Frank Li <Frank.li@nxp.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/c4ebe0503623066896d7046def4d6b1e06e0eb2e.1563972056.git.leonard.crestez@nxp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:41:31 +02:00
Linus Torvalds 4f5ed1318c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  perf_event_get(): don't bother with fget_raw()
  vfs: update d_make_root() description
2019-07-19 11:35:08 -07:00
Alexander Shishkin 8a58ddae23 perf/core: Fix exclusive events' grouping
So far, we tried to disallow grouping exclusive events for the fear of
complications they would cause with moving between contexts. Specifically,
moving a software group to a hardware context would violate the exclusivity
rules if both groups contain matching exclusive events.

This attempt was, however, unsuccessful: the check that we have in the
perf_event_open() syscall is both wrong (looks at wrong PMU) and
insufficient (group leader may still be exclusive), as can be illustrated
by running:

  $ perf record -e '{intel_pt//,cycles}' uname
  $ perf record -e '{cycles,intel_pt//}' uname

ultimately successfully.

Furthermore, we are completely free to trigger the exclusivity violation
by:

   perf -e '{cycles,intel_pt//}' -e '{intel_pt//,instructions}'

even though the helpful perf record will not allow that, the ABI will.

The warning later in the perf_event_open() path will also not trigger, because
it's also wrong.

Fix all this by validating the original group before moving, getting rid
of broken safeguards and placing a useful one to perf_install_in_context().

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: mathieu.poirier@linaro.org
Cc: will.deacon@arm.com
Fixes: bed5b25ad9 ("perf: Add a pmu capability for "exclusive" events")
Link: https://lkml.kernel.org/r/20190701110755.24646-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-13 11:21:28 +02:00
Peter Zijlstra 1cf8dfe8a6 perf/core: Fix race between close() and fork()
Syzcaller reported the following Use-after-Free bug:

	close()						clone()

							  copy_process()
							    perf_event_init_task()
							      perf_event_init_context()
							        mutex_lock(parent_ctx->mutex)
								inherit_task_group()
								  inherit_group()
								    inherit_event()
								      mutex_lock(event->child_mutex)
								      // expose event on child list
								      list_add_tail()
								      mutex_unlock(event->child_mutex)
							        mutex_unlock(parent_ctx->mutex)

							    ...
							    goto bad_fork_*

							  bad_fork_cleanup_perf:
							    perf_event_free_task()

	  perf_release()
	    perf_event_release_kernel()
	      list_for_each_entry()
		mutex_lock(ctx->mutex)
		mutex_lock(event->child_mutex)
		// event is from the failing inherit
		// on the other CPU
		perf_remove_from_context()
		list_move()
		mutex_unlock(event->child_mutex)
		mutex_unlock(ctx->mutex)

							      mutex_lock(ctx->mutex)
							      list_for_each_entry_safe()
							        // event already stolen
							      mutex_unlock(ctx->mutex)

							    delayed_free_task()
							      free_task()

	     list_for_each_entry_safe()
	       list_del()
	       free_event()
	         _free_event()
		   // and so event->hw.target
		   // is the already freed failed clone()
		   if (event->hw.target)
		     put_task_struct(event->hw.target)
		       // WHOOPSIE, already quite dead

Which puts the lie to the the comment on perf_event_free_task():
'unexposed, unused context' not so much.

Which is a 'fun' confluence of fail; copy_process() doing an
unconditional free_task() and not respecting refcounts, and perf having
creative locking. In particular:

  82d94856fa ("perf/core: Fix lock inversion between perf,trace,cpuhp")

seems to have overlooked this 'fun' parade.

Solve it by using the fact that detached events still have a reference
count on their (previous) context. With this perf_event_free_task()
can detect when events have escaped and wait for their destruction.

Debugged-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reported-by: syzbot+a24c397a29ad22d86c98@syzkaller.appspotmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 82d94856fa ("perf/core: Fix lock inversion between perf,trace,cpuhp")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-13 11:21:25 +02:00
Linus Torvalds 608745f124 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle on the kernel side were:

   - CPU PMU and uncore driver updates to Intel Snow Ridge, IceLake,
     KabyLake, AmberLake and WhiskeyLake CPUs.

   - Rework the MSR probing infrastructure to make it more robust, make
     it work better on virtualized systems and to better expose it on
     sysfs.

   - Rework PMU attributes group support based on the feedback from
     Greg. The core sysfs patch that adds sysfs_update_groups() was
     acked by Greg.

  There's a lot of perf tooling changes as well, all around the place:

   - vendor updates to Intel, cs-etm (ARM), ARM64, s390,

   - various enhancements to Intel PT tooling support:
      - Improve CBR (Core to Bus Ratio) packets support.
      - Export power and ptwrite events to sqlite and postgresql.
      - Add support for decoding PEBS via PT packets.
      - Add support for samples to contain IPC ratio, collecting cycles
        information from CYC packets, showing the IPC info periodically
      - Allow using time ranges

   - lots of updates to perf pmu, perf stat, perf trace, eBPF support,
     perf record, perf diff, etc. - please see the shortlog and Git log
     for details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (252 commits)
  tools arch x86: Sync asm/cpufeatures.h with the with the kernel
  tools build: Check if gettid() is available before providing helper
  perf jvmti: Address gcc string overflow warning for strncpy()
  perf python: Remove -fstack-protector-strong if clang doesn't have it
  perf annotate TUI browser: Do not use member from variable within its own initialization
  perf tests: Fix record+probe_libc_inet_pton.sh for powerpc64
  perf evsel: Do not rely on errno values for precise_ip fallback
  perf thread: Allow references to thread objects after machine__exit()
  perf header: Assign proper ff->ph in perf_event__synthesize_features()
  tools arch kvm: Sync kvm headers with the kernel sources
  perf script: Allow specifying the files to process guest samples
  perf tools metric: Don't include duration_time in group
  perf list: Avoid extra : for --raw metrics
  perf vendor events intel: Metric fixes for SKX/CLX
  perf tools: Fix typos / broken sentences
  perf jevents: Add support for Hisi hip08 L3C PMU aliasing
  perf jevents: Add support for Hisi hip08 HHA PMU aliasing
  perf jevents: Add support for Hisi hip08 DDRC PMU aliasing
  perf pmu: Support more complex PMU event aliasing
  perf diff: Documentation -c cycles option
  ...
2019-07-09 11:15:52 -07:00
Linus Torvalds 927ba67a63 Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The timer and timekeeping departement delivers:

  Core:

   - The consolidation of the VDSO code into a generic library including
     the conversion of x86 and ARM64. Conversion of ARM and MIPS are en
     route through the relevant maintainer trees and should end up in
     5.4.

     This gets rid of the unnecessary different copies of the same code
     and brings all architectures on the same level of VDSO
     functionality.

   - Make the NTP user space interface more robust by restricting the
     TAI offset to prevent undefined behaviour. Includes a selftest.

   - Validate user input in the compat settimeofday() syscall to catch
     invalid values which would be turned into valid values by a
     multiplication overflow

   - Consolidate the time accessors

   - Small fixes, improvements and cleanups all over the place

  Drivers:

   - Support for the NXP system counter, TI davinci timer

   - Move the Microsoft HyperV clocksource/events code into the
     drivers/clocksource directory so it can be shared between x86 and
     ARM64.

   - Overhaul of the Tegra driver

   - Delay timer support for IXP4xx

   - Small fixes, improvements and cleanups as usual"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
  time: Validate user input in compat_settimeofday()
  timer: Document TIMER_PINNED
  clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic
  clocksource/drivers: Make Hyper-V clocksource ISA agnostic
  MAINTAINERS: Fix Andy's surname and the directory entries of VDSO
  hrtimer: Use a bullet for the returns bullet list
  arm64: vdso: Fix compilation with clang older than 8
  arm64: compat: Fix __arch_get_hw_counter() implementation
  arm64: Fix __arch_get_hw_counter() implementation
  lib/vdso: Make delta calculation work correctly
  MAINTAINERS: Add entry for the generic VDSO library
  arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 system
  arm64: vdso: Remove unnecessary asm-offsets.c definitions
  vdso: Remove superfluous #ifdef __KERNEL__ in vdso/datapage.h
  clocksource/drivers/davinci: Add support for clocksource
  clocksource/drivers/davinci: Add support for clockevents
  clocksource/drivers/tegra: Set up maximum-ticks limit properly
  clocksource/drivers/tegra: Cycles can't be 0
  clocksource/drivers/tegra: Restore base address before cleanup
  clocksource/drivers/tegra: Add verbose definition for 1MHz constant
  ...
2019-07-08 11:06:29 -07:00
Ingo Molnar 552a031ba1 Linux 5.2
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0idTweHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGZesIAJDKicw2Voyx8K8m
 3pXSK+71RuO/d3Y9M51mdfTMKRP4PHR9/4wVZ9wHPwC4dV6wxgsmIYCF69a1Wety
 LD1MpDCP1DK5wVfPNKVX2xmj7ua6iutPtSsJHzdzM2TlscgsrFKjmUccqJ5JLwL5
 c34nqwXWnzzRyI5Ga9cQSlwzAXq0vDHXyML3AnCosSsLX0lKFrHlK1zttdOPNkfj
 dXRN62g3q+9kVQozzhDXb8atZZ7IkBk8Q0lujpNXW83Ci1VjaVNv3SB8GZTXIlLj
 U15VdyuwfJDfpBgFBN6/unzVaAB6FFrEKy0jT1aeTyKarMKDKgOnJjn10aKjDNno
 /bXsKKc=
 =TVqV
 -----END PGP SIGNATURE-----

Merge tag 'v5.2' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-08 18:04:41 +02:00
Al Viro 02e5ad9738 perf_event_get(): don't bother with fget_raw()
... since we immediately follow that with check that it *is* an
opened perf file, with O_PATH ones ending with with the same
-EBADF we'd get for descriptor that isn't opened at all.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-06-26 20:43:53 -04:00
Ian Rogers fd7d55172d perf/cgroups: Don't rotate events for cgroups unnecessarily
Currently perf_rotate_context assumes that if the context's nr_events !=
nr_active a rotation is necessary for perf event multiplexing. With
cgroups, nr_events is the total count of events for all cgroups and
nr_active will not include events in a cgroup other than the current
task's. This makes rotation appear necessary for cgroups when it is not.

Add a perf_event_context flag that is set when rotation is necessary.
Clear the flag during sched_out and set it when a flexible sched_in
fails due to resources.

Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20190601082722.44543-1-irogers@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:30:04 +02:00
Kan Liang e321d02db8 perf/x86: Disable extended registers for non-supported PMUs
The perf fuzzer caused Skylake machine to crash:

[ 9680.085831] Call Trace:
[ 9680.088301]  <IRQ>
[ 9680.090363]  perf_output_sample_regs+0x43/0xa0
[ 9680.094928]  perf_output_sample+0x3aa/0x7a0
[ 9680.099181]  perf_event_output_forward+0x53/0x80
[ 9680.103917]  __perf_event_overflow+0x52/0xf0
[ 9680.108266]  ? perf_trace_run_bpf_submit+0xc0/0xc0
[ 9680.113108]  perf_swevent_hrtimer+0xe2/0x150
[ 9680.117475]  ? check_preempt_wakeup+0x181/0x230
[ 9680.122091]  ? check_preempt_curr+0x62/0x90
[ 9680.126361]  ? ttwu_do_wakeup+0x19/0x140
[ 9680.130355]  ? try_to_wake_up+0x54/0x460
[ 9680.134366]  ? reweight_entity+0x15b/0x1a0
[ 9680.138559]  ? __queue_work+0x103/0x3f0
[ 9680.142472]  ? update_dl_rq_load_avg+0x1cd/0x270
[ 9680.147194]  ? timerqueue_del+0x1e/0x40
[ 9680.151092]  ? __remove_hrtimer+0x35/0x70
[ 9680.155191]  __hrtimer_run_queues+0x100/0x280
[ 9680.159658]  hrtimer_interrupt+0x100/0x220
[ 9680.163835]  smp_apic_timer_interrupt+0x6a/0x140
[ 9680.168555]  apic_timer_interrupt+0xf/0x20
[ 9680.172756]  </IRQ>

The XMM registers can only be collected by PEBS hardware events on the
platforms with PEBS baseline support, e.g. Icelake, not software/probe
events.

Add capabilities flag PERF_PMU_CAP_EXTENDED_REGS to indicate the PMU
which support extended registers. For X86, the extended registers are
XMM registers.

Add has_extended_regs() to check if extended registers are applied.

The generic code define the mask of extended registers as 0 if arch
headers haven't overridden it.

Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 878068ea27 ("perf/x86: Support outputting XMM registers")
Link: https://lkml.kernel.org/r/1559081314-9714-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:19:23 +02:00
Ravi Bangoria 913a90bc5a perf/ioctl: Add check for the sample_period value
perf_event_open() limits the sample_period to 63 bits. See:

  0819b2e30c ("perf: Limit perf_event_attr::sample_period to 63 bits")

Make ioctl() consistent with it.

Also on PowerPC, negative sample_period could cause a recursive
PMIs leading to a hang (reported when running perf-fuzzer).

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: maddy@linux.vnet.ibm.com
Cc: mpe@ellerman.id.au
Fixes: 0819b2e30c ("perf: Limit perf_event_attr::sample_period to 63 bits")
Link: https://lkml.kernel.org/r/20190604042953.914-1-ravi.bangoria@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:19:22 +02:00
Jason A. Donenfeld 9285ec4c8b timekeeping: Use proper clock specifier names in functions
This makes boot uniformly boottime and tai uniformly clocktai, to
address the remaining oversights.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lkml.kernel.org/r/20190621203249.3909-2-Jason@zx2c4.com
2019-06-22 12:11:27 +02:00
Peter Zijlstra 085ebfe937 perf/core: Fix perf_sample_regs_user() mm check
perf_sample_regs_user() uses 'current->mm' to test for the presence of
userspace, but this is insufficient, consider use_mm().

A better test is: '!(current->flags & PF_KTHREAD)', exec() clears
PF_KTHREAD after it sets the new ->mm but before it drops to userspace
for the first time.

Possibly obsoletes: bf05fc25f2 ("powerpc/perf: Fix oops when kthread execs user process")

Reported-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Reported-by: Young Xiao <92siuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4018994f3d ("perf: Add ability to attach user level registers dump to sample")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:11:58 +02:00
Jiri Olsa f3a3a8257e perf/core: Add attr_groups_update into struct pmu
Adding attr_update attribute group into pmu, to allow
having multiple attribute groups for same group name.

This will allow us to update "events" or "format"
directories with attributes that depend on various
HW conditions.

For example having group_format_extra group that updates
"format" directory only if pmu version is 2 and higher:

  static umode_t
  exra_is_visible(struct kobject *kobj, struct attribute *attr, int i)
  {
         return x86_pmu.version >= 2 ? attr->mode : 0;
  }

  static struct attribute_group group_format_extra = {
         .name       = "format",
         .is_visible = exra_is_visible,
  };

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190512155518.21468-3-jolsa@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:58:21 +02:00
Song Liu 9fd2e48b9a perf/core: Allow non-privileged uprobe for user processes
Currently, non-privileged user could only use uprobe with

    kernel.perf_event_paranoid = -1

However, setting perf_event_paranoid to -1 leaks other users' processes to
non-privileged uprobes.

To introduce proper permission control of uprobes, we are building the
following system:

  A daemon with CAP_SYS_ADMIN is in charge to create uprobes via tracefs;
  Users asks the daemon to create uprobes;
  Then user can attach uprobe only to processes owned by the user.

This patch allows non-privileged user to attach uprobe to processes owned
by the user.

The following example shows how to use uprobe with non-privileged user.
This is based on Brendan's blog post [1]

1. Create uprobe with root:

  sudo perf probe -x 'readline%return +0($retval):string'

2. Then non-root user can use the uprobe as:

  perf record -vvv -e probe_bash:readline__return -p <pid> sleep 20
  perf script

[1] http://www.brendangregg.com/blog/2015-06-28/linux-ftrace-uprobe.html

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190507161545.788381-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:58:18 +02:00
Stephane Eranian c68d224e5e perf/core: Add perf_pmu_resched() as global function
This patch add perf_pmu_resched() a global function that can be called
to force rescheduling of events for a given PMU. The function locks
both cpuctx and task_ctx internally. This will be used by a subsequent
patch.

Signed-off-by: Stephane Eranian <eranian@google.com>
[ Simplified the calling convention. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Cc: nelson.dsouza@intel.com
Cc: tonyj@suse.com
Link: https://lkml.kernel.org/r/20190408173252.37932-2-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16 12:19:34 +02:00
Ingo Molnar cc8670945d Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16 12:14:46 +02:00
Alexander Shishkin 52a44f83fc perf/core: Fix the address filtering fix
The following recent commit:

  c60f83b813 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset")

changes the address filtering logic to communicate filter ranges to the PMU driver
via a single address range object, instead of having the driver do the final bit of
math.

That change forgets to take into account kernel filters, which are not calculated
the same way as DSO based filters.

Fix that by passing the kernel filters the same way as file-based filters.
This doesn't require any additional changes in the drivers.

Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: c60f83b813 ("perf, pt, coresight: Fix address filters for vmas with non-zero offset")
Link: https://lkml.kernel.org/r/20190329091212.29870-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16 12:13:57 +02:00
Ingo Molnar 496156e364 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-16 12:02:43 +02:00
Peter Zijlstra 1d54ad9440 perf/core: Fix perf_event_disable_inatomic() race
Thomas-Mich Richter reported he triggered a WARN()ing from event_function_local()
on his s390. The problem boils down to:

	CPU-A				CPU-B

	perf_event_overflow()
	  perf_event_disable_inatomic()
	    @pending_disable = 1
	    irq_work_queue();

	sched-out
	  event_sched_out()
	    @pending_disable = 0

					sched-in
					perf_event_overflow()
					  perf_event_disable_inatomic()
					    @pending_disable = 1;
					    irq_work_queue(); // FAILS

	irq_work_run()
	  perf_pending_event()
	    if (@pending_disable)
	      perf_event_disable_local(); // WHOOPS

The problem exists in generic, but s390 is particularly sensitive
because it doesn't implement arch_irq_work_raise(), nor does it call
irq_work_run() from it's PMU interrupt handler (nor would that be
sufficient in this case, because s390 also generates
perf_event_overflow() from pmu::stop). Add to that the fact that s390
is a virtual architecture and (virtual) CPU-A can stall long enough
for the above race to happen, even if it would self-IPI.

Adding a irq_work_sync() to event_sched_in() would work for all hardare
PMUs that properly use irq_work_run() but fails for software PMUs.

Instead encode the CPU number in @pending_disable, such that we can
tell which CPU requested the disable. This then allows us to detect
the above scenario and even redirect the IPI to make up for the failed
queue.

Reported-by: Thomas-Mich Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-12 08:55:55 +02:00
Valdis Kletnieks d18bf4229b perf/core: Make perf_swevent_init_cpu() static
'make W=1' causes GCC to complain:

  kernel/events/core.c:11877:6: warning: no previous prototype for 'perf_swevent_init_cpu' [-Wmissing-prototypes]

It's not referenced anywhere else, make it static.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/28974.1552377997@turing-police
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-04-03 09:52:34 +02:00
Thomas Gleixner 4a98be8293 perf/core improvements and fixes:
kernel:
 
   Stephane Eranian :
 
   - Restore mmap record type correctly when handling PERF_RECORD_MMAP2
     events, as the same template is used for all the threads interested
     in mmap events, some may want just PERF_RECORD_MMAP, while some
     may want the extra info in MMAP2 records.
 
 perf probe:
 
   Adrian Hunter:
 
   - Fix getting the kernel map, because since changes related to x86 PTI
     entry trampolines handling, there are more than one kernel map.
 
 perf script:
 
   Andi Kleen:
 
   - Support insn output for normal samples, i.e.:
 
     perf script -F ip,sym,insn --xed
 
     Will fetch the sample IP from the thread address space and feed it
     to Intel's XED disassembler, producing lines such as:
 
       ffffffffa4068804 native_write_msr            wrmsr
       ffffffffa415b95e __hrtimer_next_event_base   movq  0x18(%rax), %rdx
 
     That match 'perf annotate's output.
 
   - Make the --cpu filter apply to  PERF_RECORD_COMM/FORK/... events, in
     addition to PERF_RECORD_SAMPLE.
 
 perf report:
 
   - Add a new --samples option to save a small random number of samples
     per hist entry, using a reservoir technique to select a representative
     number of samples.
 
     Then allow browsing the samples using 'perf script' as part of the hist
     entry context menu. This automatically adds the right filters, so only
     the thread or CPU of the sample is displayed. Then we use less' search
     functionality to directly jump to the time stamp of the selected sample.
 
     It uses different menus for assembler and source display.  Assembler
     needs xed installed and source needs debuginfo.
 
   - Fix the UI browser scripts pop up menu when there are many scripts
     available.
 
 perf report:
 
   Andi Kleen:
 
   - Add 'time' sort option. E.g.:
 
     % perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
     ...
          0.67%  277061.87300  [.] _dl_start
          0.50%  277061.87300  [.] f1
          0.50%  277061.87300  [.] f2
          0.33%  277061.87300  [.] main
          0.29%  277061.87300  [.] _dl_lookup_symbol_x
          0.29%  277061.87300  [.] dl_main
          0.29%  277061.87300  [.] do_lookup_x
          0.17%  277061.87300  [.] _dl_debug_initialize
          0.17%  277061.87300  [.] _dl_init_paths
          0.08%  277061.87300  [.] check_match
          0.04%  277061.87300  [.] _dl_count_modids
          1.33%  277061.87400  [.] f1
          1.33%  277061.87400  [.] f2
          1.33%  277061.87400  [.] main
          1.17%  277061.87500  [.] main
          1.08%  277061.87500  [.] f1
          1.08%  277061.87500  [.] f2
          1.00%  277061.87600  [.] main
          0.83%  277061.87600  [.] f1
          0.83%  277061.87600  [.] f2
          1.00%  277061.87700  [.] main
 
 tools headers:
 
   Arnaldo Carvalho de Melo:
 
   - Update x86's syscall_64.tbl, no change in tools/perf behaviour.
 
   -  Sync copies asm-generic/unistd.h and linux/in with the kernel sources.
 
 perf data:
 
   Jiri Olsa:
 
   - Prep work to support having perf.data stored as a directory, with one
     file per CPU, that ultimately will allow having one ring buffer reading
     thread per CPU.
 
 Vendor events:
 
   Martin Liška:
 
   - perf PMU events for AMD Family 17h.
 
 perf script python:
 
   Tony Jones:
 
   - Add python3 support for the remaining Intel PT related scripts, with
     these we should have a clean build of perf with python3 while still
     supporting the build with python2.
 
 libbpf:
 
   Arnaldo Carvalho de Melo:
 
   - Fix the build on uCLibc, adding the missing stdarg.h since we use
     va_list in one typedef.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXIbMlgAKCRCyPKLppCJ+
 J/fzAQDNlP1cEuryAfWCDZ/sf5N/76srvkt/kIyYO0CliCjiBAEAiHRWrhsNs1Gd
 Z8626lCTYt7BTdz5yfTb7gbt/n7xNAY=
 =Ycye
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-for-mingo-5.1-20190311' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/core improvements and fixes from Arnaldo:

kernel:

  Stephane Eranian :

  - Restore mmap record type correctly when handling PERF_RECORD_MMAP2
    events, as the same template is used for all the threads interested
    in mmap events, some may want just PERF_RECORD_MMAP, while some
    may want the extra info in MMAP2 records.

perf probe:

  Adrian Hunter:

  - Fix getting the kernel map, because since changes related to x86 PTI
    entry trampolines handling, there are more than one kernel map.

perf script:

  Andi Kleen:

  - Support insn output for normal samples, i.e.:

    perf script -F ip,sym,insn --xed

    Will fetch the sample IP from the thread address space and feed it
    to Intel's XED disassembler, producing lines such as:

      ffffffffa4068804 native_write_msr            wrmsr
      ffffffffa415b95e __hrtimer_next_event_base   movq  0x18(%rax), %rdx

    That match 'perf annotate's output.

  - Make the --cpu filter apply to  PERF_RECORD_COMM/FORK/... events, in
    addition to PERF_RECORD_SAMPLE.

perf report:

  - Add a new --samples option to save a small random number of samples
    per hist entry, using a reservoir technique to select a representative
    number of samples.

    Then allow browsing the samples using 'perf script' as part of the hist
    entry context menu. This automatically adds the right filters, so only
    the thread or CPU of the sample is displayed. Then we use less' search
    functionality to directly jump to the time stamp of the selected sample.

    It uses different menus for assembler and source display.  Assembler
    needs xed installed and source needs debuginfo.

  - Fix the UI browser scripts pop up menu when there are many scripts
    available.

perf report:

  Andi Kleen:

  - Add 'time' sort option. E.g.:

    % perf report --sort time,overhead,symbol --time-quantum 1ms --stdio
    ...
         0.67%  277061.87300  [.] _dl_start
         0.50%  277061.87300  [.] f1
         0.50%  277061.87300  [.] f2
         0.33%  277061.87300  [.] main
         0.29%  277061.87300  [.] _dl_lookup_symbol_x
         0.29%  277061.87300  [.] dl_main
         0.29%  277061.87300  [.] do_lookup_x
         0.17%  277061.87300  [.] _dl_debug_initialize
         0.17%  277061.87300  [.] _dl_init_paths
         0.08%  277061.87300  [.] check_match
         0.04%  277061.87300  [.] _dl_count_modids
         1.33%  277061.87400  [.] f1
         1.33%  277061.87400  [.] f2
         1.33%  277061.87400  [.] main
         1.17%  277061.87500  [.] main
         1.08%  277061.87500  [.] f1
         1.08%  277061.87500  [.] f2
         1.00%  277061.87600  [.] main
         0.83%  277061.87600  [.] f1
         0.83%  277061.87600  [.] f2
         1.00%  277061.87700  [.] main

tools headers:

  Arnaldo Carvalho de Melo:

  - Update x86's syscall_64.tbl, no change in tools/perf behaviour.

  -  Sync copies asm-generic/unistd.h and linux/in with the kernel sources.

perf data:

  Jiri Olsa:

  - Prep work to support having perf.data stored as a directory, with one
    file per CPU, that ultimately will allow having one ring buffer reading
    thread per CPU.

Vendor events:

  Martin Liška:

  - perf PMU events for AMD Family 17h.

perf script python:

  Tony Jones:

  - Add python3 support for the remaining Intel PT related scripts, with
    these we should have a clean build of perf with python3 while still
    supporting the build with python2.

libbpf:

  Arnaldo Carvalho de Melo:

  - Fix the build on uCLibc, adding the missing stdarg.h since we use
    va_list in one typedef.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-22 22:50:41 +01:00
Stephane Eranian d9c1bb2f6a perf/core: Restore mmap record type correctly
On mmap(), perf_events generates a RECORD_MMAP record and then checks
which events are interested in this record. There are currently 2
versions of mmap records: RECORD_MMAP and RECORD_MMAP2. MMAP2 is larger.
The event configuration controls which version the user level tool
accepts.

If the event->attr.mmap2=1 field then MMAP2 record is returned.  The
perf_event_mmap_output() takes care of this. It checks attr->mmap2 and
corrects the record fields before putting it in the sampling buffer of
the event.  At the end the function restores the modified MMAP record
fields.

The problem is that the function restores the size but not the type.
Thus, if a subsequent event only accepts MMAP type, then it would
instead receive an MMAP2 record with a size of MMAP record.

This patch fixes the problem by restoring the record type on exit.

Signed-off-by: Stephane Eranian <eranian@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Fixes: 13d7a2410f ("perf: Add attr->mmap2 attribute to an event")
Link: http://lkml.kernel.org/r/20190307185233.225521-1-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-11 11:56:02 -03:00
Linus Torvalds 12ad143e1b Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Thomas Gleixner:
 "Perf updates and fixes:

  Kernel:
   - Handle events which have the bpf_event attribute set as side band
     events as they carry information about BPF programs.
   - Add missing switch-case fall-through comments

  Libraries:
   - Fix leaks and double frees in error code paths.
   - Prevent buffer overflows in libtraceevent

  Tools:
   - Improvements in handling Intel BT/PTS
   - Add BTF ELF markers to perf trace BPF programs to improve output
   - Support --time, --cpu, --pid and --tid filters for perf diff
   - Calculate the column width in perf annotate as the hardcoded 6
     characters for the instruction are not sufficient
   - Small fixes all over the place"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  perf/core: Mark expected switch fall-through
  perf/x86/intel/uncore: Fix client IMC events return huge result
  perf/ring_buffer: Use high order allocations for AUX buffers optimistically
  perf data: Force perf_data__open|close zero data->file.path
  perf session: Fix double free in perf_data__close
  perf evsel: Probe for precise_ip with simple attr
  perf tools: Read and store caps/max_precise in perf_pmu
  perf hist: Fix memory leak of srcline
  perf hist: Add error path into hist_entry__init
  perf c2c: Fix c2c report for empty numa node
  perf script python: Add Python3 support to intel-pt-events.py
  perf script python: Add Python3 support to event_analyzing_sample.py
  perf script python: add Python3 support to check-perf-trace.py
  perf script python: Add Python3 support to futex-contention.py
  perf script python: Remove mixed indentation
  perf diff: Support --pid/--tid filter options
  perf diff: Support --cpu filter option
  perf diff: Support --time filter option
  perf thread: Generalize function to copy from thread addr space from intel-bts code
  perf annotate: Calculate the max instruction name, align column to that
  ...
2019-03-10 15:22:03 -07:00
Linus Torvalds a50243b1dd 5.1 Merge Window Pull Request
This has been a slightly more active cycle than normal with ongoing core
 changes and quite a lot of collected driver updates.
 
 - Various driver fixes for bnxt_re, cxgb4, hns, mlx5, pvrdma, rxe
 
 - A new data transfer mode for HFI1 giving higher performance
 
 - Significant functional and bug fix update to the mlx5 On-Demand-Paging MR
   feature
 
 - A chip hang reset recovery system for hns
 
 - Change mm->pinned_vm to an atomic64
 
 - Update bnxt_re to support a new 57500 chip
 
 - A sane netlink 'rdma link add' method for creating rxe devices and fixing
   the various unregistration race conditions in rxe's unregister flow
 
 - Allow lookup up objects by an ID over netlink
 
 - Various reworking of the core to driver interface:
   * Drivers should not assume umem SGLs are in PAGE_SIZE chunks
   * ucontext is accessed via udata not other means
   * Start to make the core code responsible for object memory
     allocation
   * Drivers should convert struct device to struct ib_device
     via a helper
   * Drivers have more tools to avoid use after unregister problems
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEfB7FMLh+8QxL+6i3OG33FX4gmxoFAlyAJYYACgkQOG33FX4g
 mxrWwQ/+OyAx4Moru7Aix0C6GWxTJp/wKgw21CS3reZxgLai6x81xNYG/s2wCNjo
 IccObVd7mvzyqPdxOeyHBsJBbQDqWvoD6O2duH8cqGMgBRgh3CSdUep2zLvPpSAx
 2W1SvWYCLDnCuarboFrCA8c4AN3eCZiqD7z9lHyFQGjy3nTUWzk1uBaOP46uaiMv
 w89N8EMdXJ/iY6ONzihvE05NEYbMA8fuvosKLLNdghRiHIjbMQU8SneY23pvyPDd
 ZziPu9NcO3Hw9OVbkwtJp47U3KCBgvKHmnixyZKkikjiD+HVoABw2IMwcYwyBZwP
 Bic/ddONJUvAxMHpKRnQaW7znAiHARk21nDG28UAI7FWXH/wMXgicMp6LRcNKqKF
 vqXdxHTKJb0QUR4xrYI+eA8ihstss7UUpgSgByuANJ0X729xHiJtlEvPb1DPo1Dz
 9CB4OHOVRl5O8sA5Jc6PSusZiKEpvWoyWbdmw0IiwDF5pe922VLl5Nv88ta+sJ38
 v2Ll5AgYcluk7F3599Uh9D7gwp5hxW2Ph3bNYyg2j3HP4/dKsL9XvIJPXqEthgCr
 3KQS9rOZfI/7URieT+H+Mlf+OWZhXsZilJG7No0fYgIVjgJ00h3SF1/299YIq6Qp
 9W7ZXBfVSwLYA2AEVSvGFeZPUxgBwHrSZ62wya4uFeB1jyoodPk=
 =p12E
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma updates from Jason Gunthorpe:
 "This has been a slightly more active cycle than normal with ongoing
  core changes and quite a lot of collected driver updates.

   - Various driver fixes for bnxt_re, cxgb4, hns, mlx5, pvrdma, rxe

   - A new data transfer mode for HFI1 giving higher performance

   - Significant functional and bug fix update to the mlx5
     On-Demand-Paging MR feature

   - A chip hang reset recovery system for hns

   - Change mm->pinned_vm to an atomic64

   - Update bnxt_re to support a new 57500 chip

   - A sane netlink 'rdma link add' method for creating rxe devices and
     fixing the various unregistration race conditions in rxe's
     unregister flow

   - Allow lookup up objects by an ID over netlink

   - Various reworking of the core to driver interface:
       - drivers should not assume umem SGLs are in PAGE_SIZE chunks
       - ucontext is accessed via udata not other means
       - start to make the core code responsible for object memory
         allocation
       - drivers should convert struct device to struct ib_device via a
         helper
       - drivers have more tools to avoid use after unregister problems"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (280 commits)
  net/mlx5: ODP support for XRC transport is not enabled by default in FW
  IB/hfi1: Close race condition on user context disable and close
  RDMA/umem: Revert broken 'off by one' fix
  RDMA/umem: minor bug fix in error handling path
  RDMA/hns: Use GFP_ATOMIC in hns_roce_v2_modify_qp
  cxgb4: kfree mhp after the debug print
  IB/rdmavt: Fix concurrency panics in QP post_send and modify to error
  IB/rdmavt: Fix loopback send with invalidate ordering
  IB/iser: Fix dma_nents type definition
  IB/mlx5: Set correct write permissions for implicit ODP MR
  bnxt_re: Clean cq for kernel consumers only
  RDMA/uverbs: Don't do double free of allocated PD
  RDMA: Handle ucontext allocations by IB/core
  RDMA/core: Fix a WARN() message
  bnxt_re: fix the regression due to changes in alloc_pbl
  IB/mlx4: Increase the timeout for CM cache
  IB/core: Abort page fault handler silently during owning process exit
  IB/mlx5: Validate correct PD before prefetch MR
  IB/mlx5: Protect against prefetch of invalid MR
  RDMA/uverbs: Store PR pointer before it is overwritten
  ...
2019-03-09 15:53:03 -08:00
Gustavo A. R. Silva 10c3405f06 perf: Mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch fixes the following warning:

  kernel/events/core.c: In function ‘perf_event_parse_addr_filter’:
  kernel/events/core.c:9154:11: warning: this statement may fall through [-Wimplicit-fallthrough=]
      kernel = 1;
      ~~~~~~~^~~
  kernel/events/core.c:9156:3: note: here
     case IF_SRC_FILEADDR:
     ^~~~

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kees Kook <keescook@chromium.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190212205430.GA8446@embeddedor
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-01 10:54:00 -03:00
Song Liu 21038f2baa perf, bpf: Consider events with attr.bpf_event as side-band events
Events with attr.bpf_event set should be considered as side-band events,
as they carry information about BPF programs.

Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Fixes: 6ee52e2a3f ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
Link: http://lkml.kernel.org/r/20190226002019.3748539-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-28 14:20:35 -03:00
Ingo Molnar c978b9460f perf/core improvements and fixes:
perf annotate:
 
   Wei Li:
 
   - Fix getting source line failure
 
 perf script:
 
   Andi Kleen:
 
   - Handle missing fields with -F +...
 
 perf data:
 
   Jiri Olsa:
 
   - Prep work to support per-cpu files in a directory.
 
 Intel PT:
 
   Adrian Hunter:
 
   - Improve thread_stack__no_call_return()
 
   - Hide x86 retpolines in thread stacks.
 
   - exported SQL viewer refactorings, new 'top calls' report..
 
   Alexander Shishkin:
 
   - Copy parent's address filter offsets on clone
 
   - Fix address filters for vmas with non-zero offset. Applies to
     ARM's CoreSight as well.
 
 python scripts:
 
   Tony Jones:
 
   - Python3 support for several 'perf script' python scripts.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCXHRYNwAKCRCyPKLppCJ+
 J8XmAQDKY7gb3GhkX+4aE8cGffFYB2YV5mD9Bbu4AM9tuFFBJwD+KAq87FMCy7m7
 h7xyWk3UILpz6y235AVdfOmgcNDkpAQ=
 =SJCG
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-for-mingo-5.1-20190225' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core

Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:

perf annotate:

  Wei Li:

  - Fix getting source line failure

perf script:

  Andi Kleen:

  - Handle missing fields with -F +...

perf data:

  Jiri Olsa:

  - Prep work to support per-cpu files in a directory.

Intel PT:

  Adrian Hunter:

  - Improve thread_stack__no_call_return()

  - Hide x86 retpolines in thread stacks.

  - exported SQL viewer refactorings, new 'top calls' report..

  Alexander Shishkin:

  - Copy parent's address filter offsets on clone

  - Fix address filters for vmas with non-zero offset. Applies to
    ARM's CoreSight as well.

python scripts:

  Tony Jones:

  - Python3 support for several 'perf script' python scripts.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-28 08:29:50 +01:00
Ingo Molnar 9ed8f1a6e7 Merge branch 'linus' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-28 08:27:17 +01:00
Alexander Shishkin c60f83b813 perf, pt, coresight: Fix address filters for vmas with non-zero offset
Currently, the address range calculation for file-based filters works as
long as the vma that maps the matching part of the object file starts
from offset zero into the file (vm_pgoff==0). Otherwise, the resulting
filter range would be off by vm_pgoff pages. Another related problem is
that in case of a partially matching vma, that is, a vma that matches
part of a filter region, the filter range size wouldn't be adjusted.

Fix the arithmetics around address filter range calculations, taking
into account vma offset, so that the entire calculation is done before
the filter configuration is passed to the PMU drivers instead of having
those drivers do the final bit of arithmetics.

Based on the patch by Adrian Hunter <adrian.hunter.intel.com>.

Reported-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-3-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-22 16:52:07 -03:00
Alexander Shishkin 18736eef12 perf: Copy parent's address filter offsets on clone
When a child event is allocated in the inherit_event() path, the VMA
based filter offsets are not copied from the parent, even though the
address space mapping of the new task remains the same, which leads to
no trace for the new task until exec.

Reported-by: Mansour Alharthi <malharthi9@gatech.edu>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20190215115655.63469-2-alexander.shishkin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-22 16:52:07 -03:00
Jiri Olsa 81ec3f3c4c perf/x86: Add check_period PMU callback
Vince (and later on Ravi) reported crashes in the BTS code during
fuzzing with the following backtrace:

  general protection fault: 0000 [#1] SMP PTI
  ...
  RIP: 0010:perf_prepare_sample+0x8f/0x510
  ...
  Call Trace:
   <IRQ>
   ? intel_pmu_drain_bts_buffer+0x194/0x230
   intel_pmu_drain_bts_buffer+0x160/0x230
   ? tick_nohz_irq_exit+0x31/0x40
   ? smp_call_function_single_interrupt+0x48/0xe0
   ? call_function_single_interrupt+0xf/0x20
   ? call_function_single_interrupt+0xa/0x20
   ? x86_schedule_events+0x1a0/0x2f0
   ? x86_pmu_commit_txn+0xb4/0x100
   ? find_busiest_group+0x47/0x5d0
   ? perf_event_set_state.part.42+0x12/0x50
   ? perf_mux_hrtimer_restart+0x40/0xb0
   intel_pmu_disable_event+0xae/0x100
   ? intel_pmu_disable_event+0xae/0x100
   x86_pmu_stop+0x7a/0xb0
   x86_pmu_del+0x57/0x120
   event_sched_out.isra.101+0x83/0x180
   group_sched_out.part.103+0x57/0xe0
   ctx_sched_out+0x188/0x240
   ctx_resched+0xa8/0xd0
   __perf_event_enable+0x193/0x1e0
   event_function+0x8e/0xc0
   remote_function+0x41/0x50
   flush_smp_call_function_queue+0x68/0x100
   generic_smp_call_function_single_interrupt+0x13/0x30
   smp_call_function_single_interrupt+0x3e/0xe0
   call_function_single_interrupt+0xf/0x20
   </IRQ>

The reason is that while event init code does several checks
for BTS events and prevents several unwanted config bits for
BTS event (like precise_ip), the PERF_EVENT_IOC_PERIOD allows
to create BTS event without those checks being done.

Following sequence will cause the crash:

If we create an 'almost' BTS event with precise_ip and callchains,
and it into a BTS event it will crash the perf_prepare_sample()
function because precise_ip events are expected to come
in with callchain data initialized, but that's not the
case for intel_pmu_drain_bts_buffer() caller.

Adding a check_period callback to be called before the period
is changed via PERF_EVENT_IOC_PERIOD. It will deny the change
if the event would become BTS. Plus adding also the limit_period
check as well.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190204123532.GA4794@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-11 11:46:43 +01:00
Davidlohr Bueso 70f8a3ca68 mm: make mm->pinned_vm an atomic64 counter
Taking a sleeping lock to _only_ increment a variable is quite the
overkill, and pretty much all users do this. Furthermore, some drivers
(ie: infiniband and scif) that need pinned semantics can go to quite
some trouble to actually delay via workqueue (un)accounting for pinned
pages when not possible to acquire it.

By making the counter atomic we no longer need to hold the mmap_sem and
can simply some code around it for pinned_vm users. The counter is 64-bit
such that we need not worry about overflows such as rdma user input
controlled from userspace.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-02-07 12:54:02 -07:00
Elena Reshetova ca3bb3d027 perf/ring_buffer: Convert ring_buffer.aux_refcount to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable ring_buffer.aux_refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the ring_buffer.aux_refcount it might make a difference
in following places:

 - perf_aux_output_begin(): increment in refcount_inc_not_zero() only
   guarantees control dependency on success vs. fully ordered
   atomic counterpart
 - rb_free_aux(): decrement in refcount_dec_and_test() only
   provides RELEASE ordering and ACQUIRE ordering + control dependency
   on success vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-4-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:46:17 +01:00
Elena Reshetova fecb8ed2ce perf/ring_buffer: Convert ring_buffer.refcount to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable ring_buffer.refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the ring_buffer.refcount it might make a difference
in following places:

 - ring_buffer_get(): increment in refcount_inc_not_zero() only
   guarantees control dependency on success vs. fully ordered
   atomic counterpart
 - ring_buffer_put(): decrement in refcount_dec_and_test() only
   provides RELEASE ordering and ACQUIRE ordering + control dependency
   on success vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-3-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:46:16 +01:00
Elena Reshetova 8c94abbbe1 perf: Convert perf_event_context.refcount to refcount_t
atomic_t variables are currently used to implement reference
counters with the following properties:

 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable perf_event_context.refcount is used as pure reference counter.
Convert it to refcount_t and fix up the operations.

** Important note for maintainers:

Some functions from refcount_t API defined in lib/refcount.c
have different memory ordering guarantees than their atomic
counterparts. Please check Documentation/core-api/refcount-vs-atomic.rst
for more information.

Normally the differences should not matter since refcount_t provides
enough guarantees to satisfy the refcounting use cases, but in
some rare cases it might matter.
Please double check that you don't have some undocumented
memory guarantees for this variable usage.

For the perf_event_context.refcount it might make a difference
in following places:

 - get_ctx(), perf_event_ctx_lock_nested(), perf_lock_task_context()
   and __perf_event_ctx_lock_double(): increment in
   refcount_inc_not_zero() only guarantees control dependency
   on success vs. fully ordered atomic counterpart
 - put_ctx(): decrement in refcount_dec_and_test() provides
   RELEASE ordering and ACQUIRE ordering + control dependency on success
   vs. fully ordered atomic counterpart

Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/r/1548678448-24458-2-git-send-email-elena.reshetova@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:46:15 +01:00
Thomas Gleixner 8e86e01526 perf/core: Convert to SPDX license identifiers
Use proper SPDX license identifiers instead of the bogus reference to
kernel-base/COPYING.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190116111308.012666937@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:46:11 +01:00
Ingo Molnar 98cb621081 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:45:42 +01:00
Song Liu 6ee52e2a3f perf, bpf: Introduce PERF_RECORD_BPF_EVENT
For better performance analysis of BPF programs, this patch introduces
PERF_RECORD_BPF_EVENT, a new perf_event_type that exposes BPF program
load/unload information to user space.

Each BPF program may contain up to BPF_MAX_SUBPROGS (256) sub programs.
The following example shows kernel symbols for a BPF program with 7 sub
programs:

    ffffffffa0257cf9 t bpf_prog_b07ccb89267cf242_F
    ffffffffa02592e1 t bpf_prog_2dcecc18072623fc_F
    ffffffffa025b0e9 t bpf_prog_bb7a405ebaec5d5c_F
    ffffffffa025dd2c t bpf_prog_a7540d4a39ec1fc7_F
    ffffffffa025fcca t bpf_prog_05762d4ade0e3737_F
    ffffffffa026108f t bpf_prog_db4bd11e35df90d4_F
    ffffffffa0263f00 t bpf_prog_89d64e4abf0f0126_F
    ffffffffa0257cf9 t bpf_prog_ae31629322c4b018__dummy_tracepoi

When a bpf program is loaded, PERF_RECORD_KSYMBOL is generated for each
of these sub programs. Therefore, PERF_RECORD_BPF_EVENT is not needed
for simple profiling.

For annotation, user space need to listen to PERF_RECORD_BPF_EVENT and
gather more information about these (sub) programs via sys_bpf.

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradeaed.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-4-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-21 17:00:57 -03:00
Song Liu 76193a9452 perf, bpf: Introduce PERF_RECORD_KSYMBOL
For better performance analysis of dynamically JITed and loaded kernel
functions, such as BPF programs, this patch introduces
PERF_RECORD_KSYMBOL, a new perf_event_type that exposes kernel symbol
register/unregister information to user space.

The following data structure is used for PERF_RECORD_KSYMBOL.

    /*
     * struct {
     *      struct perf_event_header        header;
     *      u64                             addr;
     *      u32                             len;
     *      u16                             ksym_type;
     *      u16                             flags;
     *      char                            name[];
     *      struct sample_id                sample_id;
     * };
     */

Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: kernel-team@fb.com
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20190117161521.1341602-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-21 17:00:57 -03:00
Arnaldo Carvalho de Melo 5620196951 perf: Make perf_event_output() propagate the output() return
For the original mode of operation it isn't needed, since we report back
errors via PERF_RECORD_LOST records in the ring buffer, but for use in
bpf_perf_event_output() it is convenient to return the errors, basically
-ENOSPC.

Currently bpf_perf_event_output() returns an error indication, the last
thing it does, which is to push it to the ring buffer is that can fail
and if so, this failure won't be reported back to its users, fix it.

Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/r/20190118150938.GN5823@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-21 17:00:57 -03:00
Andrew Murray cc6795aeff perf/core: Add PERF_PMU_CAP_NO_EXCLUDE for exclusion incapable PMUs
Many PMU drivers do not have the capability to exclude counting events
that occur in specific contexts such as idle, kernel, guest, etc. These
drivers indicate this by returning an error in their event_init upon
testing the events attribute flags. This approach is error prone and
often inconsistent.

Let's instead allow PMU drivers to advertise their inability to exclude
based on context via a new capability: PERF_PMU_CAP_NO_EXCLUDE. This
allows the perf core to reject requests for exclusion events where
there is no support in the PMU.

Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-4-git-send-email-andrew.murray@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:01:20 +01:00
Stephane Eranian 1a51c5da5a perf core: Fix perf_proc_update_handler() bug
The perf_proc_update_handler() handles /proc/sys/kernel/perf_event_max_sample_rate
syctl variable.  When the PMU IRQ handler timing monitoring is disabled, i.e,
when /proc/sys/kernel/perf_cpu_time_max_percent is equal to 0 or 100,
then no modification to sysctl_perf_event_sample_rate is allowed to prevent
possible hang from wrong values.

The problem is that the test to prevent modification is made after the
sysctl variable is modified in perf_proc_update_handler().

You get an error:

  $ echo 10001 >/proc/sys/kernel/perf_event_max_sample_rate
  echo: write error: invalid argument

But the value is still modified causing all sorts of inconsistencies:

  $ cat /proc/sys/kernel/perf_event_max_sample_rate
  10001

This patch fixes the problem by moving the parsing of the value after
the test.

Committer testing:

  # echo 100 > /proc/sys/kernel/perf_cpu_time_max_percent
  # echo 10001 > /proc/sys/kernel/perf_event_max_sample_rate
  -bash: echo: write error: Invalid argument
  # cat /proc/sys/kernel/perf_event_max_sample_rate
  10001
  #

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1547169436-6266-1-git-send-email-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-01-18 11:10:38 -03:00
Linus Torvalds 96d4f267e4 Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 18:57:57 -08:00
Linus Torvalds 116b081c28 Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "The main changes in this cycle on the kernel side:

   - rework kprobes blacklist handling (Masami Hiramatsu)

   - misc cleanups

  on the tooling side these areas were the main focus:

   - 'perf trace'     enhancements (Arnaldo Carvalho de Melo)

   - 'perf bench'     enhancements (Davidlohr Bueso)

   - 'perf record'    enhancements (Alexey Budankov)

   - 'perf annotate'  enhancements (Jin Yao)

   - 'perf top'       enhancements (Jiri Olsa)

   - Intel hw tracing enhancements (Adrian Hunter)

   - ARM hw tracing   enhancements (Leo Yan, Mathieu Poirier)

   - ... plus lots of other enhancements, cleanups and fixes"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (171 commits)
  tools uapi asm: Update asm-generic/unistd.h copy
  perf symbols: Relax checks on perf-PID.map ownership
  perf trace: Wire up the fadvise 'advice' table generator
  perf beauty: Add generator for fadvise64's 'advice' arg constants
  tools headers uapi: Grab a copy of fadvise.h
  perf beauty mmap: Print mmap's 'offset' arg in hexadecimal
  perf beauty mmap: Print PROT_READ before PROT_EXEC to match strace output
  perf trace beauty: Beautify arch_prctl()'s arguments
  perf trace: When showing string prefixes show prefix + ??? for unknown entries
  perf trace: Move strarrays to beauty.h for further reuse
  perf beauty: Wire up the x86_arch prctl code table generator
  perf beauty: Add a string table generator for x86's 'arch_prctl' codes
  tools include arch: Grab a copy of x86's prctl.h
  perf trace: Show NULL when syscall pointer args are 0
  perf trace: Enclose the errno strings with ()
  perf augmented_raw_syscalls: Copy 'access' arg as well
  perf trace: Add alignment spaces after the closing parens
  perf trace beauty: Print O_RDONLY when (flags & O_ACCMODE) == 0
  perf trace: Allow asking for not suppressing common string prefixes
  perf trace: Add a prefix member to the strarray class
  ...
2018-12-26 14:45:18 -08:00
Ingo Molnar fca0c11650 perf: Fix typos in comments
Fix two typos in kernel/events/*.

No change in functionality intended.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-03 11:22:32 +01:00
Paul E. McKenney 0809d95451 events: Replace synchronize_sched() with synchronize_rcu()
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu().  This commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
2018-11-27 09:21:44 -08:00
Linus Torvalds 01897f3e05 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates and fixes from Ingo Molnar:
 "These are almost all tooling updates: 'perf top', 'perf trace' and
  'perf script' fixes and updates, an UAPI header sync with the merge
  window versions, license marker updates, much improved Sparc support
  from David Miller, and a number of fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (66 commits)
  perf intel-pt/bts: Calculate cpumode for synthesized samples
  perf intel-pt: Insert callchain context into synthesized callchains
  perf tools: Don't clone maps from parent when synthesizing forks
  perf top: Start display thread earlier
  tools headers uapi: Update linux/if_link.h header copy
  tools headers uapi: Update linux/netlink.h header copy
  tools headers: Sync the various kvm.h header copies
  tools include uapi: Update linux/mmap.h copy
  perf trace beauty: Use the mmap flags table generated from headers
  perf beauty: Wire up the mmap flags table generator to the Makefile
  perf beauty: Add a generator for MAP_ mmap's flag constants
  tools include uapi: Update asound.h copy
  tools arch uapi: Update asm-generic/unistd.h and arm64 unistd.h copies
  tools include uapi: Update linux/fs.h copy
  perf callchain: Honour the ordering of PERF_CONTEXT_{USER,KERNEL,etc}
  perf cs-etm: Correct CPU mode for samples
  perf unwind: Take pgoff into account when reporting elf to libdwfl
  perf top: Do not use overwrite mode by default
  perf top: Allow disabling the overwrite mode
  perf trace: Beautify mount's first pathname arg
  ...
2018-11-03 18:13:43 -07:00
Linus Torvalds 343a9f3540 The biggest change here is the updates to kprobes
Back in January I posted patches to create function based events. These were
 the events that you suggested I make to allow developers to easily create
 events in code where no trace event exists. After posting those changes for
 review, it was suggested that we implement this instead with kprobes.
 
 The problem with kprobes is that the interface is too complex and needs to
 be simplified. Masami Hiramatsu posted patches in March and I've been
 playing with them a bit. There's been a bit of clean up in the kprobe code
 that was inspired by the function based event patches, and a couple of
 enhancements to the kprobe event interface.
 
  - If the arch supports it (we added support for x86), you can place a
    kprobe event at the start of a function and use $arg1, $arg2, etc
    to reference the arguments of a function. (Before you needed to know
    what register or where on the stack the argument was).
 
  - The second is a way to see array of events. For example, if you reference
    a mac address, you can add:
 
    echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events
 
    And this will produce:
 
    mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}
 
 Other changes include
 
  - Exporting trace_dump_stack to modules
 
  - Have the stack tracer trace the entire stack (stop trying to remove
    tracing itself, as we keep removing too much).
 
  - Added support for SDT in uprobes
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCW9hdjxQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qmtbAP9GS/o2WSvsYLSIw4+mF94eCL06lUxp
 rRrktkEofm/PagEAl2JNmvHrAJN+LIrajqXTbwlZ7Ckk1rZhCW41Am7qnQs=
 =sTUM
 -----END PGP SIGNATURE-----

Merge tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The biggest change here is the updates to kprobes

  Back in January I posted patches to create function based events.
  These were the events that you suggested I make to allow developers to
  easily create events in code where no trace event exists. After
  posting those changes for review, it was suggested that we implement
  this instead with kprobes.

  The problem with kprobes is that the interface is too complex and
  needs to be simplified. Masami Hiramatsu posted patches in March and
  I've been playing with them a bit. There's been a bit of clean up in
  the kprobe code that was inspired by the function based event patches,
  and a couple of enhancements to the kprobe event interface.

   - If the arch supports it (we added support for x86), you can place a
     kprobe event at the start of a function and use $arg1, $arg2, etc
     to reference the arguments of a function. (Before you needed to
     know what register or where on the stack the argument was).

   - The second is a way to see array of events. For example, if you
     reference a mac address, you can add:

	echo 'p:mac ip_rcv perm_addr=+574($arg2):x8[6]' > kprobe_events

     And this will produce:

	mac: (ip_rcv+0x0/0x140) perm_addr={0x52,0x54,0x0,0xc0,0x76,0xec}

  Other changes include

   - Exporting trace_dump_stack to modules

   - Have the stack tracer trace the entire stack (stop trying to remove
     tracing itself, as we keep removing too much).

   - Added support for SDT in uprobes"

[ SDT - "Statically Defined Tracing" are userspace markers for tracing.
  Let's not use random TLA's in explanations unless they are fairly
  well-established as generic (at least for kernel people) - Linus ]

* tag 'trace-v4.20' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (24 commits)
  tracing: Have stack tracer trace full stack
  tracing: Export trace_dump_stack to modules
  tracing: probeevent: Fix uninitialized used of offset in parse args
  tracing/kprobes: Allow kprobe-events to record module symbol
  tracing/kprobes: Check the probe on unloaded module correctly
  tracing/uprobes: Fix to return -EFAULT if copy_from_user failed
  tracing: probeevent: Add $argN for accessing function args
  x86: ptrace: Add function argument access API
  tracing: probeevent: Add array type support
  tracing: probeevent: Add symbol type
  tracing: probeevent: Unify fetch_insn processing common part
  tracing: probeevent: Append traceprobe_ for exported function
  tracing: probeevent: Return consumed bytes of dynamic area
  tracing: probeevent: Unify fetch type tables
  tracing: probeevent: Introduce new argument fetching code
  tracing: probeevent: Remove NOKPROBE_SYMBOL from print functions
  tracing: probeevent: Cleanup argument field definition
  tracing: probeevent: Cleanup print argument functions
  trace_uprobe: support reference counter in fd-based uprobe
  perf probe: Support SDT markers having reference counter (semaphore)
  ...
2018-10-30 09:49:56 -07:00
Colin Ian King 28fa741c27 perf/core: Clean up inconsisent indentation
Replace a bunch of spaces with tab, cleans up indentation

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-janitors@vger.kernel.org
Link: http://lkml.kernel.org/r/20181029233211.21475-1-colin.king@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-30 09:51:58 +01:00
Song Liu a6ca88b241 trace_uprobe: support reference counter in fd-based uprobe
This patch enables uprobes with reference counter in fd-based uprobe.
Highest 32 bits of perf_event_attr.config is used to stored offset
of the reference count (semaphore).

Format information in /sys/bus/event_source/devices/uprobe/format/ is
updated to reflect this new feature.

Link: http://lkml.kernel.org/r/20181002053636.1896903-1-songliubraving@fb.com

Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-and-tested-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-10 22:14:17 -04:00
Jiri Olsa cd6fb677ce perf/ring_buffer: Prevent concurent ring buffer access
Some of the scheduling tracepoints allow the perf_tp_event
code to write to ring buffer under different cpu than the
code is running on.

This results in corrupted ring buffer data demonstrated in
following perf commands:

  # perf record -e 'sched:sched_switch,sched:sched_wakeup' perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

       Total time: 0.383 [sec]
  [ perf record: Woken up 8 times to write data ]
  0x42b890 [0]: failed to process type: -1765585640
  [ perf record: Captured and wrote 4.825 MB perf.data (29669 samples) ]

  # perf report --stdio
  0x42b890 [0]: failed to process type: -1765585640

The reason for the corruption are some of the scheduling tracepoints,
that have __perf_task dfined and thus allow to store data to another
cpu ring buffer:

  sched_waking
  sched_wakeup
  sched_wakeup_new
  sched_stat_wait
  sched_stat_sleep
  sched_stat_iowait
  sched_stat_blocked

The perf_tp_event function first store samples for current cpu
related events defined for tracepoint:

    hlist_for_each_entry_rcu(event, head, hlist_entry)
      perf_swevent_event(event, count, &data, regs);

And then iterates events of the 'task' and store the sample
for any task's event that passes tracepoint checks:

  ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]);

  list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
    if (event->attr.type != PERF_TYPE_TRACEPOINT)
      continue;
    if (event->attr.config != entry->type)
      continue;

    perf_swevent_event(event, count, &data, regs);
  }

Above code can race with same code running on another cpu,
ending up with 2 cpus trying to store under the same ring
buffer, which is specifically not allowed.

This patch prevents the problem, by allowing only events with the same
current cpu to receive the event.

NOTE: this requires the use of (per-task-)per-cpu buffers for this
feature to work; perf-record does this.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
[peterz: small edits to Changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: e6dab5ffab ("perf/trace: Add ability to set a target task for events")
Link: http://lkml.kernel.org/r/20180923161343.GB15054@krava
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02 09:37:59 +02:00
Peter Zijlstra a9f9772114 perf/core: Fix perf_pmu_unregister() locking
When we unregister a PMU, we fail to serialize the @pmu_idr properly.
Fix that by doing the entire thing under pmu_lock.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 2e80a82a49 ("perf: Dynamic pmu types")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-02 09:37:56 +02:00
Reinette Chatre befb1b3c27 perf/core: Add sanity check to deal with pinned event failure
It is possible that a failure can occur during the scheduling of a
pinned event. The initial portion of perf_event_read_local() contains
the various error checks an event should pass before it can be
considered valid. Ensure that the potential scheduling failure
of a pinned event is checked for and have a credible error.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: fenghua.yu@intel.com
Cc: tony.luck@intel.com
Cc: acme@kernel.org
Cc: gavin.hindman@intel.com
Cc: jithu.joseph@intel.com
Cc: dave.hansen@intel.com
Cc: hpa@zytor.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/6486385d1f30336e9973b24c8c65f5079543d3d3.1537377064.git.reinette.chatre@intel.com
2018-09-28 22:44:53 +02:00
Yabin Cui 02e184476e perf/core: Force USER_DS when recording user stack data
Perf can record user stack data in response to a synchronous request, such
as a tracepoint firing. If this happens under set_fs(KERNEL_DS), then we
end up reading user stack data using __copy_from_user_inatomic() under
set_fs(KERNEL_DS). I think this conflicts with the intention of using
set_fs(KERNEL_DS). And it is explicitly forbidden by hardware on ARM64
when both CONFIG_ARM64_UAO and CONFIG_ARM64_PAN are used.

So fix this by forcing USER_DS when recording user stack data.

Signed-off-by: Yabin Cui <yabinc@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 88b0193d94 ("perf/callchain: Force USER_DS when invoking perf_callchain_user()")
Link: http://lkml.kernel.org/r/20180823225935.27035-1-yabinc@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-10 14:01:46 +02:00
Ingo Molnar fa94351b56 perf/urgent fixes:
Kernel:
 
 - Modify breakpoint fixes (Jiri Olsa)
 
 perf annotate:
 
 - Fix parsing aarch64 branch instructions after objdump update (Kim Phillips)
 
 - Fix parsing indirect calls in 'perf annotate' (Martin Liška)
 
 perf probe:
 
 - Ignore SyS symbols irrespective of endianness on PowerPC (Sandipan Das)
 
 perf trace:
 
 - Fix include path for asm-generic/unistd.h on arm64 (Kim Phillips)
 
 Core libraries:
 
 - Fix potential null pointer dereference in perf_evsel__new_idx() (Hisao Tanabe)
 
 - Use fixed size string for comms instead of scanf("%m"), that is
   not present in the bionic libc and leads to a crash (Chris Phlipot)
 
 - Fix bad memory access in trace info on 32-bit systems, we were reading
   8 bytes from a 4-byte long variable when saving the command line in the
   perf.data file.  (Chris Phlipot)
 
 Build system:
 
 - Streamline bpf examples and headers installation, clarifying
   some install messages. (Arnaldo Carvalho de Melo)
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQR2GiIUctdOfX2qHhGyPKLppCJ+JwUCW41FnAAKCRCyPKLppCJ+
 J8MCAP4/RC5GwNrO5KYJ+G1iYb7QiNq9X/wsM7jCBlqWnTH+zgD9GYPIT3WQWKBN
 Rv94N4PNsYP4cpP7hTzWG0ar7p70owo=
 =+ODq
 -----END PGP SIGNATURE-----

Merge tag 'perf-urgent-for-mingo-4.19-20180903' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

Kernel:

- Modify breakpoint fixes (Jiri Olsa)

perf annotate:

- Fix parsing aarch64 branch instructions after objdump update (Kim Phillips)

- Fix parsing indirect calls in 'perf annotate' (Martin Liška)

perf probe:

- Ignore SyS symbols irrespective of endianness on PowerPC (Sandipan Das)

perf trace:

- Fix include path for asm-generic/unistd.h on arm64 (Kim Phillips)

Core libraries:

- Fix potential null pointer dereference in perf_evsel__new_idx() (Hisao Tanabe)

- Use fixed size string for comms instead of scanf("%m"), that is
  not present in the bionic libc and leads to a crash (Chris Phlipot)

- Fix bad memory access in trace info on 32-bit systems, we were reading
  8 bytes from a 4-byte long variable when saving the command line in the
  perf.data file.  (Chris Phlipot)

Build system:

- Streamline bpf examples and headers installation, clarifying
  some install messages. (Arnaldo Carvalho de Melo)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-09-09 21:36:31 +02:00
Jiri Olsa bf06278c3f perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint
We can safely enable the breakpoint back for both the fail and success
paths by checking only the bp->attr.disabled, which either holds the new
'requested' disabled state or the original breakpoint state.

Committer testing:

At the end of the series, the 'perf test' entry introduced as the first
patch now runs to completion without finding the fixed issues:

  # perf test "bp modify"
  62: x86 bp modify                                         : Ok
  #

In verbose mode:

  # perf test -v "bp modify"
  62: x86 bp modify                                         :
  --- start ---
  test child forked, pid 5161
  rip 5950a0, bp_1 0x5950a0
  in bp_1
  rip 5950a0, bp_1 0x5950a0
  in bp_1
  test child finished with 0
  ---- end ----
  x86 bp modify: Ok

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Milind Chabbi <chabbi.milind@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180827091228.2878-6-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-08-30 14:49:24 -03:00
Linus Torvalds 0214f46b3a Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull core signal handling updates from Eric Biederman:
 "It was observed that a periodic timer in combination with a
  sufficiently expensive fork could prevent fork from every completing.
  This contains the changes to remove the need for that restart.

  This set of changes is split into several parts:

   - The first part makes PIDTYPE_TGID a proper pid type instead
     something only for very special cases. The part starts using
     PIDTYPE_TGID enough so that in __send_signal where signals are
     actually delivered we know if the signal is being sent to a a group
     of processes or just a single process.

   - With that prep work out of the way the logic in fork is modified so
     that fork logically makes signals received while it is running
     appear to be received after the fork completes"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
  signal: Don't send signals to tasks that don't exist
  signal: Don't restart fork when signals come in.
  fork: Have new threads join on-going signal group stops
  fork: Skip setting TIF_SIGPENDING in ptrace_init_task
  signal: Add calculate_sigpending()
  fork: Unconditionally exit if a fatal signal is pending
  fork: Move and describe why the code examines PIDNS_ADDING
  signal: Push pid type down into complete_signal.
  signal: Push pid type down into __send_signal
  signal: Push pid type down into send_signal
  signal: Pass pid type into do_send_sig_info
  signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
  signal: Pass pid type into group_send_sig_info
  signal: Pass pid and pid type into send_sigqueue
  posix-timers: Noralize good_sigevent
  signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
  pid: Implement PIDTYPE_TGID
  pids: Move the pgrp and session pid pointers from task_struct to signal_struct
  kvm: Don't open code task_pid in kvm_vcpu_ioctl
  pids: Compute task_tgid using signal->leader_pid
  ...
2018-08-21 13:47:29 -07:00
Linus Torvalds 1202f4fdbc arm64 updates for 4.19
A bunch of good stuff in here:
 
 - Wire up support for qspinlock, replacing our trusty ticket lock code
 
 - Add an IPI to flush_icache_range() to ensure that stale instructions
   fetched into the pipeline are discarded along with the I-cache lines
 
 - Support for the GCC "stackleak" plugin
 
 - Support for restartable sequences, plus an arm64 port for the selftest
 
 - Kexec/kdump support on systems booting with ACPI
 
 - Rewrite of our syscall entry code in C, which allows us to zero the
   GPRs on entry from userspace
 
 - Support for chained PMU counters, allowing 64-bit event counters to be
   constructed on current CPUs
 
 - Ensure scheduler topology information is kept up-to-date with CPU
   hotplug events
 
 - Re-enable support for huge vmalloc/IO mappings now that the core code
   has the correct hooks to use break-before-make sequences
 
 - Miscellaneous, non-critical fixes and cleanups
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABCgAGBQJbbV41AAoJELescNyEwWM0WoEIALhrKtsIn6vqFlSs/w6aDuJL
 cMWmFxjTaKLmIq2+cJIdFLOJ3CH80Pu9gB+nEv/k+cZdCTfUVKfRf28HTpmYWsht
 bb4AhdHMC7yFW752BHk+mzJspeC8h/2Rm8wMuNVplZ3MkPrwo3vsiuJTofLhVL/y
 BihlU3+5sfBvCYIsWnuEZIev+/I/s/qm1ASiqIcKSrFRZP6VTt5f9TC75vFI8seW
 7yc3odKb0CArexB8yBjiPNziehctQF42doxQyL45hezLfWw4qdgHOSiwyiOMxEz9
 Fwwpp8Tx33SKLNJgqoqYznGW9PhYJ7n2Kslv19uchJrEV+mds82vdDNaWRULld4=
 =kQn6
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "A bunch of good stuff in here. Worth noting is that we've pulled in
  the x86/mm branch from -tip so that we can make use of the core
  ioremap changes which allow us to put down huge mappings in the
  vmalloc area without screwing up the TLB. Much of the positive
  diffstat is because of the rseq selftest for arm64.

  Summary:

   - Wire up support for qspinlock, replacing our trusty ticket lock
     code

   - Add an IPI to flush_icache_range() to ensure that stale
     instructions fetched into the pipeline are discarded along with the
     I-cache lines

   - Support for the GCC "stackleak" plugin

   - Support for restartable sequences, plus an arm64 port for the
     selftest

   - Kexec/kdump support on systems booting with ACPI

   - Rewrite of our syscall entry code in C, which allows us to zero the
     GPRs on entry from userspace

   - Support for chained PMU counters, allowing 64-bit event counters to
     be constructed on current CPUs

   - Ensure scheduler topology information is kept up-to-date with CPU
     hotplug events

   - Re-enable support for huge vmalloc/IO mappings now that the core
     code has the correct hooks to use break-before-make sequences

   - Miscellaneous, non-critical fixes and cleanups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (90 commits)
  arm64: alternative: Use true and false for boolean values
  arm64: kexec: Add comment to explain use of __flush_icache_range()
  arm64: sdei: Mark sdei stack helper functions as static
  arm64, kaslr: export offset in VMCOREINFO ELF notes
  arm64: perf: Add cap_user_time aarch64
  efi/libstub: Only disable stackleak plugin for arm64
  arm64: drop unused kernel_neon_begin_partial() macro
  arm64: kexec: machine_kexec should call __flush_icache_range
  arm64: svc: Ensure hardirq tracing is updated before return
  arm64: mm: Export __sync_icache_dcache() for xen-privcmd
  drivers/perf: arm-ccn: Use devm_ioremap_resource() to map memory
  arm64: Add support for STACKLEAK gcc plugin
  arm64: Add stack information to on_accessible_stack
  drivers/perf: hisi: update the sccl_id/ccl_id when MT is supported
  arm64: fix ACPI dependencies
  rseq/selftests: Add support for arm64
  arm64: acpi: fix alignment fault in accessing ACPI
  efi/arm: map UEFI memory map even w/o runtime services enabled
  efi/arm: preserve early mapping of UEFI memory map longer for BGRT
  drivers: acpi: add dependency of EFI for arm64
  ...
2018-08-14 16:39:13 -07:00
Michael O'Farrell 9d2dcc8fc6 arm64: perf: Add cap_user_time aarch64
It is useful to get the running time of a thread.  Doing so in an
efficient manner can be important for performance of user applications.
Avoiding system calls in `clock_gettime` when handling
CLOCK_THREAD_CPUTIME_ID is important.  Other clocks are handled in the
VDSO, but CLOCK_THREAD_CPUTIME_ID falls back on the system call.

CLOCK_THREAD_CPUTIME_ID is not handled in the VDSO since it would have
costs associated with maintaining updated user space accessible time
offsets.  These offsets have to be updated everytime the a thread is
scheduled/descheduled.  However, for programs regularly checking the
running time of a thread, this is a performance improvement.

This patch takes a middle ground, and adds support for cap_user_time an
optional feature of the perf_event API.  This way costs are only
incurred when the perf_event api is enabled.  This is done the same way
as it is in x86.

Ultimately this allows calculating the thread running time in userspace
on aarch64 as follows (adapted from perf_event_open manpage):

u32 seq, time_mult, time_shift;
u64 running, count, time_offset, quot, rem, delta;
struct perf_event_mmap_page *pc;
pc = buf;  // buf is the perf event mmaped page as documented in the API.

if (pc->cap_usr_time) {
    do {
        seq = pc->lock;
        barrier();
        running = pc->time_running;

        count = readCNTVCT_EL0();  // Read ARM hardware clock.
        time_offset = pc->time_offset;
        time_mult   = pc->time_mult;
        time_shift  = pc->time_shift;

        barrier();
    } while (pc->lock != seq);

    quot = (count >> time_shift);
    rem = count & (((u64)1 << time_shift) - 1);
    delta = time_offset + quot * time_mult +
            ((rem * time_mult) >> time_shift);

    running += delta;
    // running now has the current nanosecond level thread time.
}

Summary of changes in the patch:

For aarch64 systems, make arch_perf_update_userpage update the timing
information stored in the perf_event page.  Requiring the following
calculations:
  - Calculate the appropriate time_mult, and time_shift factors to convert
    ticks to nano seconds for the current clock frequency.
  - Adjust the mult and shift factors to avoid shift factors of 32 bits.
    (possibly unnecessary)
  - The time_offset userspace should apply when doing calculations:
    negative the current sched time (now), because time_running and
    time_enabled fields of the perf_event page have just been updated.
Toggle bits to appropriate values:
  - Enable cap_user_time

Signed-off-by: Michael O'Farrell <micpof@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-31 10:14:00 +01:00
Ingo Molnar 93081caaae Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:47:02 +02:00
Mathieu Poirier 7f635ff187 perf/core: Fix crash when using HW tracing kernel filters
In function perf_event_parse_addr_filter(), the path::dentry of each struct
perf_addr_filter is left unassigned (as it should be) when the pattern
being parsed is related to kernel space.  But in function
perf_addr_filter_match() the same dentries are given to d_inode() where
the value is not expected to be NULL, resulting in the following splat:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
  pc : perf_event_mmap+0x2fc/0x5a0
  lr : perf_event_mmap+0x2c8/0x5a0
  Process uname (pid: 2860, stack limit = 0x000000001cbcca37)
  Call trace:
   perf_event_mmap+0x2fc/0x5a0
   mmap_region+0x124/0x570
   do_mmap+0x344/0x4f8
   vm_mmap_pgoff+0xe4/0x110
   vm_mmap+0x2c/0x40
   elf_map+0x60/0x108
   load_elf_binary+0x450/0x12c4
   search_binary_handler+0x90/0x290
   __do_execve_file.isra.13+0x6e4/0x858
   sys_execve+0x3c/0x50
   el0_svc_naked+0x30/0x34

This patch is fixing the problem by introducing a new check in function
perf_addr_filter_match() to see if the filter's dentry is NULL.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: miklos@szeredi.hu
Cc: namhyung@kernel.org
Cc: songliubraving@fb.com
Fixes: 9511bce9fe ("perf/core: Fix bad use of igrab()")
Link: http://lkml.kernel.org/r/1531782831-1186-1-git-send-email-mathieu.poirier@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:46:22 +02:00
Peter Zijlstra 6cbc304f2f perf/x86/intel: Fix unwind errors from PEBS entries (mk-II)
Vince reported the perf_fuzzer giving various unwinder warnings and
Josh reported:

> Deja vu.  Most of these are related to perf PEBS, similar to the
> following issue:
>
>   b8000586c9 ("perf/x86/intel: Cure bogus unwind from PEBS entries")
>
> This is basically the ORC version of that.  setup_pebs_sample_data() is
> assembling a franken-pt_regs which ORC isn't happy about.  RIP is
> inconsistent with some of the other registers (like RSP and RBP).

And where the previous unwinder only needed BP,SP ORC also requires
IP. But we cannot spoof IP because then the sample will get displaced,
entirely negating the point of PEBS.

So cure the whole thing differently by doing the unwind early; this
does however require a means to communicate we did the unwind early.
We (ab)use an unused sample_type bit for this, which we set on events
that fill out the data->callchain before the normal
perf_prepare_sample().

Debugged-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Tested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-25 11:46:21 +02:00
Eric W. Biederman 6883f81aac pid: Implement PIDTYPE_TGID
Everywhere except in the pid array we distinguish between a tasks pid and
a tasks tgid (thread group id).  Even in the enumeration we want that
distinction sometimes so we have added __PIDTYPE_TGID.  With leader_pid
we almost have an implementation of PIDTYPE_TGID in struct signal_struct.

Add PIDTYPE_TGID as a first class member of the pid_type enumeration and
into the pids array.  Then remove the __PIDTYPE_TGID special case and the
leader_pid in signal_struct.

The net size increase is just an extra pointer added to struct pid and
an extra pair of pointers of an hlist_node added to task_struct.

The effect on code maintenance is the removal of a number of special
cases today and the potential to remove many more special cases as
PIDTYPE_TGID gets used to it's fullest.  The long term potential
is allowing zombie thread group leaders to exit, which will remove
a lot more special cases in the code.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-07-21 10:43:12 -05:00
Tobias Tefke 788faab70d perf, tools: Use correct articles in comments
Some of the comments in the perf events code use articles incorrectly,
using 'a' for words beginning with a vowel sound, where 'an' should be
used.

Signed-off-by: Tobias Tefke <tobias.tefke@tutanota.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: alexander.shishkin@linux.intel.com
Cc: jolsa@redhat.com
Cc: namhyung@kernel.org
Link: http://lkml.kernel.org/r/20180709105715.22938-1-tobias.tefke@tutanota.com
[ Fix a few more perf related 'a event' typo fixes from all around the kernel and tooling tree. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16 00:21:03 +02:00
Mathieu Malaterre 9331510135 perf/core: Move inline keyword at the beginning of declaration
Fix non-fatal warning triggered during compilation with W=1:

  kernel/events/core.c:6106:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
   static void __always_inline
   ^~~~~~

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180626202301.20270-1-malat@debian.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-27 09:55:58 +02:00
Souptick Joarder 9e3ed2d759 perf/core: Change perf_mmap_fault() return type to 'vm_fault_t'
Use new return type 'vm_fault_t' for fault handlers.

For now, this is just documenting that the function returns
a VM_FAULT value rather than an errno. Once all instances
are converted, vm_fault_t will become a distinct type.

See the following commit:

  1c8f422059 ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: akpm@linux-foundation.org
Cc: alexander.shishkin@linux.intel.com
Cc: jolsa@redhat.com
Cc: namhyung@kernel.org
Link: https://lkml.kernel.org/lkml/20180521182520.GA19677@jordon-HP-15-Notebook-PC
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21 16:26:25 +02:00
Linus Torvalds 1c8c5a9d38 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...
2018-06-06 18:39:49 -07:00
Eugene Syromiatnikov 82489c5fe5 perf/core: Wire up compat PERF_EVENT_IOC_QUERY_BPF, PERF_EVENT_IOC_MODIFY_ATTRIBUTES
Since pointer size is different in compat, and switching in _perf_ioctl
is done using exact ioctl numbers, all new ioctl numbers that use pointer
should be added to perf_compat_ioctl for _IOC_SIZE fixup before passing
to perf_ioctl routine (this shouldn't be needed if semantics of the size
argument of _IO* macros was honored).

Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20180521123420.GA24291@asgard.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25 08:11:11 +02:00
Song Liu 9511bce9fe perf/core: Fix bad use of igrab()
As Miklos reported and suggested:

 "This pattern repeats two times in trace_uprobe.c and in
  kernel/events/core.c as well:

      ret = kern_path(filename, LOOKUP_FOLLOW, &path);
      if (ret)
          goto fail_address_parse;

      inode = igrab(d_inode(path.dentry));
      path_put(&path);

  And it's wrong.  You can only hold a reference to the inode if you
  have an active ref to the superblock as well (which is normally
  through path.mnt) or holding s_umount.

  This way unmounting the containing filesystem while the tracepoint is
  active will give you the "VFS: Busy inodes after unmount..." message
  and a crash when the inode is finally put.

  Solution: store path instead of inode."

This patch fixes the issue in kernel/event/core.c.

Reviewed-and-tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 375637bc52 ("perf/core: Introduce address range filtering")
Link: http://lkml.kernel.org/r/20180418062907.3210386-2-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25 08:11:10 +02:00
Song Liu a1150c2022 perf/core: Fix group scheduling with mixed hw and sw events
When hw and sw events are mixed in the same group, they are all attached
to the hw perf_event_context. This sometimes requires moving group of
perf_event to a different context.

We found a bug in how the kernel handles this, for example if we do:

   perf stat -e '{faults,ref-cycles,faults}'  -I 1000

     1.005591180              1,297      faults
     1.005591180        457,476,576      ref-cycles
     1.005591180    <not supported>      faults

First, sw event "faults" is attached to the sw context, and becomes the
group leader. Then, hw event "ref-cycles" is attached, so both events
are moved to the hw context. Last, another sw "faults" tries to attach,
but it fails because of mismatch between the new target ctx (from sw
pmu) and the group_leader's ctx (hw context, same as ref-cycles).

The broken condition is:
   group_leader is sw event;
   group_leader is on hw context;
   add a sw event to the group.

Fix this scenario by checking group_leader's context (instead of just
event type). If group_leader is on hw context, use the ->pmu of this
context to look up context for the new event.

Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: b04243ef70 ("perf: Complete software pmu grouping")
Link: http://lkml.kernel.org/r/20180503194716.162815-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-25 08:11:10 +02:00
Yonghong Song f8d959a5b1 perf/core: add perf_get_event() to return perf_event given a struct file
A new extern function, perf_get_event(), is added to return a perf event
given a struct file. This function will be used in later patches.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-24 18:18:19 -07:00
Jiri Olsa 78b562fbfa perf: Return proper values for user stack errors
Return immediately when we find issue in the user stack checks. The
error value could get overwritten by following check for
PERF_SAMPLE_REGS_INTR.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Cc: x86@kernel.org
Fixes: 60e2364e60 ("perf: Add ability to sample machine state on interrupt")
Link: http://lkml.kernel.org/r/20180415092352.12403-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:39 -03:00
Alexey Budankov 101592b490 perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]
Store preempting context switch out event into Perf trace as a part of
PERF_RECORD_SWITCH[_CPU_WIDE] record.

Percentage of preempting and non-preempting context switches help
understanding the nature of workloads (CPU or IO bound) that are running
on a machine;

The event is treated as preemption one when task->state value of the
thread being switched out is TASK_RUNNING. Event type encoding is
implemented using PERF_RECORD_MISC_SWITCH_OUT_PREEMPT bit;

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/9ff84e83-a0ca-dd82-a6d0-cb951689be74@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:39 -03:00
Song Liu 32e6e967fb perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()
Non-root user cannot create kprobe or uprobe through the text-based
interface (kprobe_events, uprobe_events),so they should not be able
to create probes via perf_event_open() either.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 33ea4b2427 ("perf/core: Implement the 'perf_uprobe' PMU")
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Link: http://lkml.kernel.org/r/C0B2EFB5-C403-4BDB-9046-C14B3EE66999@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:55:50 +02:00
Prashant Bhole 621b6d2ea2 perf/core: Fix use-after-free in uprobe_perf_close()
A use-after-free bug was caught by KASAN while running usdt related
code (BCC project. bcc/tests/python/test_usdt2.py):

	==================================================================
	BUG: KASAN: use-after-free in uprobe_perf_close+0x222/0x3b0
	Read of size 4 at addr ffff880384f9b4a4 by task test_usdt2.py/870

	CPU: 4 PID: 870 Comm: test_usdt2.py Tainted: G        W         4.16.0-next-20180409 #215
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
	Call Trace:
	 dump_stack+0xc7/0x15b
	 ? show_regs_print_info+0x5/0x5
	 ? printk+0x9c/0xc3
	 ? kmsg_dump_rewind_nolock+0x6e/0x6e
	 ? uprobe_perf_close+0x222/0x3b0
	 print_address_description+0x83/0x3a0
	 ? uprobe_perf_close+0x222/0x3b0
	 kasan_report+0x1dd/0x460
	 ? uprobe_perf_close+0x222/0x3b0
	 uprobe_perf_close+0x222/0x3b0
	 ? probes_open+0x180/0x180
	 ? free_filters_list+0x290/0x290
	 trace_uprobe_register+0x1bb/0x500
	 ? perf_event_attach_bpf_prog+0x310/0x310
	 ? probe_event_disable+0x4e0/0x4e0
	 perf_uprobe_destroy+0x63/0xd0
	 _free_event+0x2bc/0xbd0
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ring_buffer_attach+0x550/0x550
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? perf_event_release_kernel+0x3e4/0xc00
	 ? __mutex_unlock_slowpath+0x12e/0x540
	 ? wait_for_completion+0x430/0x430
	 ? lock_downgrade+0x3c0/0x3c0
	 ? lock_release+0x980/0x980
	 ? do_raw_spin_trylock+0x118/0x150
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 perf_event_release_kernel+0x5d4/0xc00
	 ? put_event+0x30/0x30
	 ? fsnotify+0xd2d/0xea0
	 ? sched_clock_cpu+0x18/0x1a0
	 ? __fsnotify_update_child_dentry_flags.part.0+0x1b0/0x1b0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? pvclock_read_flags+0x80/0x80
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? sched_clock_cpu+0x18/0x1a0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? locks_remove_file+0xec/0x470
	 ? pvclock_read_flags+0x80/0x80
	 ? fcntl_setlk+0x880/0x880
	 ? ima_file_free+0x8d/0x390
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ima_file_check+0x110/0x110
	 ? fsnotify+0xea0/0xea0
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? rcu_note_context_switch+0x600/0x600
	 perf_release+0x21/0x40
	 __fput+0x264/0x620
	 ? fput+0xf0/0xf0
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 ? SyS_fchdir+0x100/0x100
	 ? fsnotify+0xea0/0xea0
	 task_work_run+0x14b/0x1e0
	 ? task_work_cancel+0x1c0/0x1c0
	 ? copy_fd_bitmaps+0x150/0x150
	 ? vfs_read+0xe5/0x260
	 exit_to_usermode_loop+0x17b/0x1b0
	 ? trace_event_raw_event_sys_exit+0x1a0/0x1a0
	 do_syscall_64+0x3f6/0x490
	 ? syscall_return_slowpath+0x2c0/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? syscall_return_slowpath+0x1a3/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? prepare_exit_to_usermode+0x11c/0x1e0
	 ? enter_from_user_mode+0x30/0x30
	random: crng init done
	 ? __put_user_4+0x1c/0x30
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
	RIP: 0033:0x7f41d95f9340
	RSP: 002b:00007fffe71e4268 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
	RAX: 0000000000000000 RBX: 000000000000000d RCX: 00007f41d95f9340
	RDX: 0000000000000000 RSI: 0000000000002401 RDI: 000000000000000d
	RBP: 0000000000000000 R08: 00007f41ca8ff700 R09: 00007f41d996dd1f
	R10: 00007fffe71e41e0 R11: 0000000000000246 R12: 00007fffe71e4330
	R13: 0000000000000000 R14: fffffffffffffffc R15: 00007fffe71e4290

	Allocated by task 870:
	 kasan_kmalloc+0xa0/0xd0
	 kmem_cache_alloc_node+0x11a/0x430
	 copy_process.part.19+0x11a0/0x41c0
	 _do_fork+0x1be/0xa20
	 do_syscall_64+0x198/0x490
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

	Freed by task 0:
	 __kasan_slab_free+0x12e/0x180
	 kmem_cache_free+0x102/0x4d0
	 free_task+0xfe/0x160
	 __put_task_struct+0x189/0x290
	 delayed_put_task_struct+0x119/0x250
	 rcu_process_callbacks+0xa6c/0x1b60
	 __do_softirq+0x238/0x7ae

	The buggy address belongs to the object at ffff880384f9b480
	 which belongs to the cache task_struct of size 12928

It occurs because task_struct is freed before perf_event which refers
to the task and task flags are checked while teardown of the event.
perf_event_alloc() assigns task_struct to hw.target of perf_event,
but there is no reference counting for it.

As a fix we get_task_struct() in perf_event_alloc() at above mentioned
assignment and put_task_struct() in _free_event().

Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 63b6da39bb ("perf: Fix perf_event_exit_task() race")
Link: http://lkml.kernel.org/r/20180409100346.6416-1-bhole_prashant_q7@lab.ntt.co.jp
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-09 18:15:58 +02:00
Alexander Shishkin 6ed70cf342 perf/x86/pt, coresight: Clean up address filter structure
This is a cosmetic patch that deals with the address filter structure's
ambiguous fields 'filter' and 'range'. The former stands to mean that the
filter's *action* should be to filter the traces to its address range if
it's set or stop tracing if it's unset. This is confusing and hard on the
eyes, so this patch replaces it with 'action' enum. The 'range' field is
completely redundant (meaning that the filter is an address range as
opposed to a single address trigger), as we can use zero size to mean the
same thing.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180329120648.11902-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-29 16:07:22 +02:00
Ingo Molnar 7054e4e0b1 Merge branch 'perf/urgent' into perf/core, to pick up fixes
With the cherry-picked perf/urgent commit merged separately we can now
merge all the fixes without conflicts.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-24 09:21:47 +01:00
Song Liu c917e0f259 perf/cgroup: Fix child event counting bug
When a perf_event is attached to parent cgroup, it should count events
for all children cgroups:

   parent_group   <---- perf_event
     \
      - child_group  <---- process(es)

However, in our tests, we found this perf_event cannot report reliable
results. Here is an example case:

  # create cgroups
  mkdir -p /sys/fs/cgroup/p/c
  # start perf for parent group
  perf stat -e instructions -G "p"

  # on another console, run test process in child cgroup:
  stressapptest -s 2 -M 1000 & echo $! > /sys/fs/cgroup/p/c/cgroup.procs

  # after the test process is done, stop perf in the first console shows

       <not counted>      instructions              p

The instruction should not be "not counted" as the process runs in the
child cgroup.

We found this is because perf_event->cgrp and cpuctx->cgrp are not
identical, thus perf_event->cgrp are not updated properly.

This patch fixes this by updating perf_cgroup properly for ancestor
cgroup(s).

Reported-by: Ephraim Park <ephiepark@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <jolsa@redhat.com>
Cc: <kernel-team@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20180312165943.1057894-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20 08:58:47 +01:00
Ingo Molnar 134933e557 Linux 4.16-rc6
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlqvCPYeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGOaAH/171cgZGFEXSONxK
 3O1AAv61wN5K/ISMt6mnelWR6fZg195FarOx0Rnq7Ot8OWuVa8CGcyT4vX4Z7nb9
 SVMQKNMPCVQE4WCDOv6S0njChmRC0BxBoVJtTN9fhywdYgX1KcaTS/drMRHACF5n
 rB9eouMQScfMzKGAW08gp5NvEGJ6W1SLX7La3/u0751dYisdJSP7+vFZNxUrGXEA
 yIPOQjFu0Tfo8GXz/BwC678RZVzVLN0sE6+/vM7zNnoDlsRVkdDIVMo3UiVqm/NK
 B37/TlZz8CYoapoKnRRB5giXnSPDSXtsikbGy3mcy0u5imGe+ZgdjrdYSaLk31cR
 NVZY08k=
 =pu3X
 -----END PGP SIGNATURE-----

Merge tag 'v4.16-rc6' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-19 20:37:35 +01:00
Mark Rutland 24868367cd perf/core: Clear sibling list of detached events
When perf_group_dettach() is called on a group leader, it updates each
sibling's group_leader field to point to that sibling, effectively
upgrading each siblnig to a group leader. After perf_group_detach has
completed, the caller may free the leader event.

We only remove siblings from the group leader's sibling_list when the
leader has a non-empty group_node. This was fine prior to commit:

  8343aae661 ("perf/core: Remove perf_event::group_entry")

... as the sibling's sibling_list would be empty. However, now that we
use the sibling_list field as both the list head and the list entry,
this leaves each sibling with a non-empty sibling list, including the
stale leader event.

If perf_group_detach() is subsequently called on a sibling, it will
appear to be a group leader, and we'll walk the sibling_list,
potentially dereferencing these stale events. In 0day testing, this has
been observed to result in kernel panics.

Let's avoid this by always removing siblings from the sibling list when
we promote them to leaders.

Fixes: 8343aae661 ("perf/core: Remove perf_event::group_entry")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: vincent.weaver@maine.edu
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: torvalds@linux-foundation.org
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: valery.cherepennikov@intel.com
Cc: linux-tip-commits@vger.kernel.org
Cc: eranian@google.com
Cc: acme@redhat.com
Cc: alexander.shishkin@linux.intel.com
Cc: davidcc@google.com
Cc: kan.liang@intel.com
Cc: Dmitry.Prohorov@intel.com
Cc: Jiri Olsa <jolsa@redhat.com>
Link: https://lkml.kernel.org/r/20180316131741.3svgr64yibc6vsid@lakrids.cambridge.arm.com
2018-03-16 20:44:32 +01:00