flush_scheduled_work() is just a simple call to flush_work().
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Reading to wq->unbound_attrs requires protection of either wq_pool_mutex
or wq->mutex, and wq_sysfs_prep_attrs() is called with wq_pool_mutex held,
so we don't need to grab wq->mutex here.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This pre-declaration was unneeded since a previous refactor patch
6ba94429c8 ("workqueue: Reorder sysfs code").
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Current modification to attrs via sysfs is not fully synchronized.
Process A (change cpumask) | Process B (change numa affinity)
wq_cpumask_store() |
wq_sysfs_prep_attrs() |
| apply_workqueue_attrs()
apply_workqueue_attrs() |
It results that the Process B's operation is totally reverted
without any notification, it is a buggy behavior. So this patch
moves wq_sysfs_prep_attrs() into the protection under wq_pool_mutex
to ensure attrs changes are properly synchronized.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Applying attrs requires two locks: get_online_cpus() and wq_pool_mutex,
and this code is duplicated at two places (apply_workqueue_attrs() and
workqueue_set_unbound_cpumask()). So we separate out this locking
code into apply_wqattrs_[un]lock() and do a minor refactor on
apply_workqueue_attrs().
The apply_wqattrs_[un]lock() will be also used on later patch for
ensuring attrs changes are properly synchronized.
tj: minor updates to comments
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
wq_update_unbound_numa() is known be called with wq_pool_mutex held.
But wq_update_unbound_numa() requests wq->mutex before reading
wq->unbound_attrs, wq->numa_pwq_tbl[] and wq->dfl_pwq. But these fields
were changed to be allowed being read with wq_pool_mutex held. So we
simply remove the mutex_lock(&wq->mutex).
Without the dependence on the the mutex_lock(&wq->mutex), the test
of wq->unbound_attrs->no_numa can also be moved upward.
The old code need a long comment to describe the stableness of
@wq->unbound_attrs which is also guaranteed by wq_pool_mutex now,
so we don't need this such comment.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Current wq_pool_mutex doesn't proctect the attrs-installation, it results
that ->unbound_attrs, ->numa_pwq_tbl[] and ->dfl_pwq can only be accessed
under wq->mutex and causes some inconveniences. Example, wq_update_unbound_numa()
has to acquire wq->mutex before fetching the wq->unbound_attrs->no_numa
and the old_pwq.
attrs-installation is a short operation, so this change will no cause any
latency for other operations which also acquire the wq_pool_mutex.
The only unprotected attrs-installation code is in apply_workqueue_attrs(),
so this patch touches code less than comments.
It is also a preparation patch for next several patches which read
wq->unbound_attrs, wq->numa_pwq_tbl[] and wq->dfl_pwq with
only wq_pool_mutex held.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Allow to modify the low-level unbound workqueues cpumask through
sysfs. This is performed by traversing the entire workqueue list
and calling apply_wqattrs_prepare() on the unbound workqueues
with the new low level mask. Only after all the preparation are done,
we commit them all together.
Ordered workqueues are ignored from the low level unbound workqueue
cpumask, it will be handled in near future.
All the (default & per-node) pwqs are mandatorily controlled by
the low level cpumask. If the user configured cpumask doesn't overlap
with the low level cpumask, the low level cpumask will be used for the
wq instead.
The comment of wq_calc_node_cpumask() is updated and explicitly
requires that its first argument should be the attrs of the default
pwq.
The default wq_unbound_cpumask is cpu_possible_mask. The workqueue
subsystem doesn't know its best default value, let the system manager
or the other subsystem set it when needed.
Changed from V8:
merge the calculating code for the attrs of the default pwq together.
minor change the code&comments for saving the user configured attrs.
remove unnecessary list_del().
minor update the comment of wq_calc_node_cpumask().
update the comment of workqueue_set_unbound_cpumask();
Cc: Christoph Lameter <cl@linux.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mike Galbraith <bitbucket@online.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Original-patch-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Create a cpumask that limits the affinity of all unbound workqueues.
This cpumask is controlled through a file at the root of the workqueue
sysfs directory.
It works on a lower-level than the per WQ_SYSFS workqueues cpumask files
such that the effective cpumask applied for a given unbound workqueue is
the intersection of /sys/devices/virtual/workqueue/$WORKQUEUE/cpumask and
the new /sys/devices/virtual/workqueue/cpumask file.
This patch implements the basic infrastructure and the read interface.
wq_unbound_cpumask is initially set to cpu_possible_mask.
Cc: Christoph Lameter <cl@linux.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mike Galbraith <bitbucket@online.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Current apply_workqueue_attrs() includes pwqs-allocation and pwqs-installation,
so when we batch multiple apply_workqueue_attrs()s as a transaction, we can't
ensure the transaction must succeed or fail as a complete unit.
To solve this, we split apply_workqueue_attrs() into three stages.
The first stage does the preparation: allocation memory, pwqs.
The second stage does the attrs-installaion and pwqs-installation.
The third stage frees the allocated memory and (old or unused) pwqs.
As the result, batching multiple apply_workqueue_attrs()s can
succeed or fail as a complete unit:
1) batch do all the first stage for all the workqueues
2) only commit all when all the above succeed.
This patch is a preparation for the next patch ("Allow modifying low level
unbound workqueue cpumask") which will do a multiple apply_workqueue_attrs().
The patch doesn't have functionality changed except two minor adjustment:
1) free_unbound_pwq() for the error path is removed, we use the
heavier version put_pwq_unlocked() instead since the error path
is rare. this adjustment simplifies the code.
2) the memory-allocation is also moved into wq_pool_mutex.
this is needed to avoid to do the further splitting.
tj: minor updates to comments.
Suggested-by: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Mike Galbraith <bitbucket@online.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
Pull audit fixes from Paul Moore:
"Seven audit patches for v4.1, all bug fixes.
The largest, and perhaps most significant commit helps resolve some
memory pressure issues related to the inode cache and audit, there are
also a few small commits which help resolve some timing issues with
the audit log queue, and the rest fall into the always popular "code
clean-up" category.
In general, nothing really substantial, just a nice set of maintenance
patches"
* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
audit: Remove condition which always evaluates to false
audit: reduce mmap_sem hold for mm->exe_file
audit: consolidate handling of mm->exe_file
audit: code clean up
audit: don't reset working wait time accidentally with auditd
audit: don't lose set wait time on first successful call to audit_log_start()
audit: move the tree pruning to a dedicated thread
The first is a bug when ftrace_dump_on_oops is triggered in atomic context
and function graph tracer is the tracer that is being reported.
The second fix is bad parsing of the trace_events from the kernel
command line, where it would ignore specific events if the system
name is used with defining the event(it enables all events within the
system).
The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was missing
to see if the ptr was incremented to the end of the string, but the loop
increments it again and can miss the nul delimiter to stop processing.
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Merge tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This adds three fixes for the tracing code.
The first is a bug when ftrace_dump_on_oops is triggered in atomic
context and function graph tracer is the tracer that is being
reported.
The second fix is bad parsing of the trace_events from the kernel
command line, where it would ignore specific events if the system name
is used with defining the event(it enables all events within the
system).
The last one is a fix to the TRACE_DEFINE_ENUM(), where a check was
missing to see if the ptr was incremented to the end of the string,
but the loop increments it again and can miss the nul delimiter to
stop processing"
* tag 'trace-v4.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix possible out of bounds memory access when parsing enums
tracing: Fix incorrect enabling of trace events by boot cmdline
tracing: Handle ftrace_dump() atomic context in graph_trace_open()
but most architectures seem fixed now. Thanks to all involved.
Last minute rebase because I noticed a "[PATCH]" had snuck into a commit
message somehow.
Cheers,
Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull module updates from Rusty Russell:
"Quentin opened a can of worms by adding extable entry checking to
modpost, but most architectures seem fixed now. Thanks to all
involved.
Last minute rebase because I noticed a "[PATCH]" had snuck into a
commit message somehow"
* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
modpost: don't emit section mismatch warnings for compiler optimizations
modpost: expand pattern matching to support substring matches
modpost: do not try to match the SHT_NUL section.
modpost: fix extable entry size calculation.
modpost: fix inverted logic in is_extable_fault_address().
modpost: handle -ffunction-sections
modpost: Whitelist .text.fixup and .exception.text
params: handle quotes properly for values not of form foo="bar".
modpost: document the use of struct section_check.
modpost: handle relocations mismatch in __ex_table.
scripts: add check_extable.sh script.
modpost: mismatch_handler: retrieve tosym information only when needed.
modpost: factorize symbol pretty print in get_pretty_name().
modpost: add handler function pointer to sectioncheck.
modpost: add .sched.text and .kprobes.text to the TEXT_SECTIONS list.
modpost: add strict white-listing when referencing sections.
module: do not print allocation-fail warning on bogus user buffer size
kernel/module.c: fix typos in message about unused symbols
Here's the big char/misc driver patchset for 4.1-rc1.
Lots of different driver subsystem updates here, nothing major, full
details are in the shortlog below.
All of this has been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here's the big char/misc driver patchset for 4.1-rc1.
Lots of different driver subsystem updates here, nothing major, full
details are in the shortlog.
All of this has been in linux-next for a while"
* tag 'char-misc-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (133 commits)
mei: trace: remove unused TRACE_SYSTEM_STRING
DTS: ARM: OMAP3-N900: Add lis3lv02d support
Documentation: DT: lis302: update wakeup binding
lis3lv02d: DT: add wakeup unit 2 and wakeup threshold
lis3lv02d: DT: use s32 to support negative values
Drivers: hv: hv_balloon: correctly handle num_pages>INT_MAX case
Drivers: hv: hv_balloon: correctly handle val.freeram<num_pages case
mei: replace check for connection instead of transitioning
mei: use mei_cl_is_connected consistently
mei: fix mei_poll operation
hv_vmbus: Add gradually increased delay for retries in vmbus_post_msg()
Drivers: hv: hv_balloon: survive ballooning request with num_pages=0
Drivers: hv: hv_balloon: eliminate jumps in piecewiese linear floor function
Drivers: hv: hv_balloon: do not online pages in offline blocks
hv: remove the per-channel workqueue
hv: don't schedule new works in vmbus_onoffer()/vmbus_onoffer_rescind()
hv: run non-blocking message handlers in the dispatch tasklet
coresight: moving to new "hwtracing" directory
coresight-tmc: Adding a status interface to sysfs
coresight: remove the unnecessary configuration coresight-default-sink
...
Here's the big tty/serial driver update for 4.1-rc1.
It was delayed for a bit due to some questions surrounding some of the
console command line parsing changes that are in here. There's still
one tiny regression for people who were previously putting multiple
console command lines and expecting them all to be ignored for some odd
reason, but Peter is working on fixing that. If not, I'll send a revert
for the offending patch, but I have faith that Peter can address it.
Other than the console work here, there's the usual serial driver
updates and changes, and a buch of 8250 reworks to try to make that
driver easier to maintain over time, and have it support more devices in
the future.
All of these have been in linux-next for a while.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial updates from Greg KH:
"Here's the big tty/serial driver update for 4.1-rc1.
It was delayed for a bit due to some questions surrounding some of the
console command line parsing changes that are in here. There's still
one tiny regression for people who were previously putting multiple
console command lines and expecting them all to be ignored for some
odd reason, but Peter is working on fixing that. If not, I'll send a
revert for the offending patch, but I have faith that Peter can
address it.
Other than the console work here, there's the usual serial driver
updates and changes, and a buch of 8250 reworks to try to make that
driver easier to maintain over time, and have it support more devices
in the future.
All of these have been in linux-next for a while"
* tag 'tty-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (119 commits)
n_gsm: Drop unneeded cast on netdev_priv
sc16is7xx: expose RTS inversion in RS-485 mode
serial: 8250_pci: port failed after wakeup from S3
earlycon: 8250: Document kernel command line options
earlycon: 8250: Fix command line regression
earlycon: Fix __earlycon_table stride
tty: clean up the tty time logic a bit
serial: 8250_dw: only get the clock rate in one place
serial: 8250_dw: remove useless ACPI ID check
dmaengine: hsu: move memory allocation to GFP_NOWAIT
dmaengine: hsu: remove redundant pieces of code
serial: 8250_pci: add Intel Tangier support
dmaengine: hsu: add Intel Tangier PCI ID
serial: 8250_pci: replace switch-case by formula for Intel MID
serial: 8250_pci: replace switch-case by formula
tty: cpm_uart: replace CONFIG_8xx by CONFIG_CPM1
serial: jsm: some off by one bugs
serial: xuartps: Fix check in console_setup().
serial: xuartps: Get rid of register access macros.
serial: xuartps: Fix iobase use.
...
Commit 8053871d0f ("smp: Fix smp_call_function_single_async()
locking") fixed the locking for the asynchronous smp-call case, but in
the process of moving the lock handling around, one of the error cases
ended up not unlocking the call data at all.
This went unnoticed on x86, because this is a "caller is buggy" case,
where the caller is trying to call a non-existent CPU. But apparently
ARM does that (at least under qemu-arm). Bindly doing cross-cpu calls
to random CPU's that aren't even online seems a bit fishy, but the error
handling was clearly not correct.
Simply add the missing "csd_unlock()" to the error path.
Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Analyzed-by: Rabin Vincent <rabin@rab.in>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull locking fixes from Ingo Molnar:
"Two fixes: an smp-call fix and a lockdep fix"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Fix smp_call_function_single_async() locking
lockdep: Make print_lock() robust against concurrent release
Pull networking fixes from David Miller:
1) Fix verifier memory corruption and other bugs in BPF layer, from
Alexei Starovoitov.
2) Add a conservative fix for doing BPF properly in the BPF classifier
of the packet scheduler on ingress. Also from Alexei.
3) The SKB scrubber should not clear out the packet MARK and security
label, from Herbert Xu.
4) Fix oops on rmmod in stmmac driver, from Bryan O'Donoghue.
5) Pause handling is not correct in the stmmac driver because it
doesn't take into consideration the RX and TX fifo sizes. From
Vince Bridgers.
6) Failure path missing unlock in FOU driver, from Wang Cong.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits)
net: dsa: use DEVICE_ATTR_RW to declare temp1_max
netns: remove BUG_ONs from net_generic()
IB/ipoib: Fix ndo_get_iflink
sfc: Fix memcpy() with const destination compiler warning.
altera tse: Fix network-delays and -retransmissions after high throughput.
net: remove unused 'dev' argument from netif_needs_gso()
act_mirred: Fix bogus header when redirecting from VLAN
inet_diag: fix access to tcp cc information
tcp: tcp_get_info() should fetch socket fields once
net: dsa: mv88e6xxx: Add missing initialization in mv88e6xxx_set_port_state()
skbuff: Do not scrub skb mark within the same name space
Revert "net: Reset secmark when scrubbing packet"
bpf: fix two bugs in verification logic when accessing 'ctx' pointer
bpf: fix bpf helpers to use skb->mac_header relative offsets
stmmac: Configure Flow Control to work correctly based on rxfifo size
stmmac: Enable unicast pause frame detect in GMAC Register 6
stmmac: Read tx-fifo-depth and rx-fifo-depth from the devicetree
stmmac: Add defines and documentation for enabling flow control
stmmac: Add properties for transmit and receive fifo sizes
stmmac: fix oops on rmmod after assigning ip addr
...
The code that replaces the enum names with the enum values in the
tracepoints' format files could possible miss the end of string nul
character. This was caused by processing things like backslashes, quotes
and other tokens. After processing the tokens, a check for the nul
character needed to be done before continuing the loop, because the loop
incremented the pointer before doing the check, which could bypass the nul
character.
Link: http://lkml.kernel.org/r/552E661D.5060502@oracle.com
Reported-by: Sasha Levin <sasha.levin@oracle.com> # via KASan
Tested-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Fixes: 0c564a538a "tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values"
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
sync_buffer() needs the mmap_sem for two distinct operations, both only
occurring upon user context switch handling:
1) Dealing with the exe_file.
2) Adding the dcookie data as we need to lookup the vma that
backs it. This is done via add_sample() and add_data().
This patch isolates 1), for it will no longer need the mmap_sem for
serialization. However, for now, make of the more standard
get_mm_exe_file(), requiring only holding the mmap_sem to read the value,
and relying on reference counting to make sure that the exe file won't
dissappear underneath us while doing the get dcookie.
As a consequence, for 2) we move the mmap_sem locking into where we really
need it, in lookup_dcookie(). The benefits are twofold: reduce mmap_sem
hold times, and cleaner code.
[akpm@linux-foundation.org: export get_mm_exe_file for arch/x86/oprofile/oprofile.ko]
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Robert Richter <rric@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When converting unsigned long to int overflows may occur. These currently
are not detected when writing to the sysctl file system.
E.g. on a system where int has 32 bits and long has 64 bits
echo 0x800001234 > /proc/sys/kernel/threads-max
has the same effect as
echo 0x1234 > /proc/sys/kernel/threads-max
The patch adds the missing check in do_proc_dointvec_conv.
With the patch an overflow will result in an error EINVAL when writing to
the the sysctl file system.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg cleverly suggested using xchg() to set the new mm->exe_file instead
of calling set_mm_exe_file() which requires some form of serialization --
mmap_sem in this case. For archs that do not have atomic rmw instructions
we still fallback to a spinlock alternative, so this should always be
safe. As such, we only need the mmap_sem for looking up the backing
vm_file, which can be done sharing the lock. Naturally, this means we
need to manually deal with both the new and old file reference counting,
and we need not worry about the MMF_EXE_FILE_CHANGED bits, which can
probably be deleted in the future anyway.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes mm->mmap_sem from mm->exe_file read side.
Also it kills dup_mm_exe_file() and moves exe_file duplication into
dup_mmap() where both mmap_sems are locked.
[akpm@linux-foundation.org: fix comment typo]
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Users can change the maximum number of threads by writing to
/proc/sys/kernel/threads-max.
With the patch the value entered is checked against the same limits that
apply when fork_init is called.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the
THREAD_SIZE.
E.g. architecture hexagon may have page size 1M and thread size 4096.
This would lead to a division by zero in the calculation of max_threads.
With 32-bit calculation there is no solution which delivers valid results
for all possible combinations of the parameters. The code is only called
once. Hence a 64-bit calculation can be used as solution.
[akpm@linux-foundation.org: use clamp_t(), per Oleg]
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the
THREAD_SIZE.
E.g. architecture hexagon may have page size 1M and thread size 4096.
This would lead to a division by zero in the calculation of max_threads.
With this patch the buggy code is moved to a separate function
set_max_threads. The error is not fixed.
After fixing the problem in a separate patch the new function can be
reused to adjust max_threads after adding or removing memory.
Argument mempages of function fork_init() is removed as totalram_pages is
an exported symbol.
The creation of separate patches for refactoring to a new function and for
fixing the logic was suggested by Ingo Molnar.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The comment explaining what value max_threads is set to is outdated. The
maximum memory consumption ratio for thread structures was 1/2 until
February 2002, then it was briefly changed to 1/16 before being set to 1/8
which we still use today. The comment was never updated to reflect that
change, it's about time.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
copy_process will report any failure in alloc_pid as ENOMEM currently
which is misleading because the pid allocation might fail not only when
the memory is short but also when the pid space is consumed already.
The current man page even mentions this case:
: EAGAIN
:
: A system-imposed limit on the number of threads was encountered.
: There are a number of limits that may trigger this error: the
: RLIMIT_NPROC soft resource limit (set via setrlimit(2)), which
: limits the number of processes and threads for a real user ID, was
: reached; the kernel's system-wide limit on the number of processes
: and threads, /proc/sys/kernel/threads-max, was reached (see
: proc(5)); or the maximum number of PIDs, /proc/sys/kernel/pid_max,
: was reached (see proc(5)).
so the current behavior is also incorrect wrt. documentation. POSIX man
page also suggest returing EAGAIN when the process count limit is reached.
This patch simply propagates error code from alloc_pid and makes sure we
return -EAGAIN due to reservation failure. This will make behavior of
fork closer to both our documentation and POSIX.
alloc_pid might alsoo fail when the reaper in the pid namespace is dead
(the namespace basically disallows all new processes) and there is no
good error code which would match documented ones. We have traditionally
returned ENOMEM for this case which is misleading as well but as per
Eric W. Biederman this behavior is documented in man pid_namespaces(7)
: If the "init" process of a PID namespace terminates, the kernel
: terminates all of the processes in the namespace via a SIGKILL signal.
: This behavior reflects the fact that the "init" process is essential for
: the correct operation of a PID namespace. In this case, a subsequent
: fork(2) into this PID namespace will fail with the error ENOMEM; it is
: not possible to create a new processes in a PID namespace whose "init"
: process has terminated.
and introducing a new error code would be too risky so let's stick to
ENOMEM for this case.
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sending SI_TKILL from rt_[tg]sigqueueinfo was deprecated, so now we issue
a warning on the first attempt of doing it. We use WARN_ON_ONCE, which is
not informative and, what is worse, taints the kernel, making the trinity
syscall fuzzer complain false-positively from time to time.
It does not look like we need this warning at all, because the behaviour
changed quite a long time ago (2.6.39), and if an application relies on
the old API, it gets EPERM anyway and can issue a warning by itself.
So let us zap the warning in kernel.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ptrace_detach() re-checks ->ptrace under tasklist lock and calls
release_task() if __ptrace_detach() returns true. This was needed because
the __TASK_TRACED tracee could be killed/untraced, and it could even pass
exit_notify() before we take tasklist_lock.
But this is no longer possible after 9899d11f65 "ptrace: ensure
arch_ptrace/ptrace_request can never race with SIGKILL". We can turn
these checks into WARN_ON() and remove release_task().
While at it, document the setting of child->exit_code.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Pavel Labath <labath@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ptrace_resume() is called when the tracee is still __TASK_TRACED. We set
tracee->exit_code and then wake_up_state() changes tracee->state. If the
tracer's sub-thread does wait() in between, task_stopped_code(ptrace => T)
wrongly looks like another report from tracee.
This confuses debugger, and since wait_task_stopped() clears ->exit_code
the tracee can miss a signal.
Test-case:
#include <stdio.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/ptrace.h>
#include <pthread.h>
#include <assert.h>
int pid;
void *waiter(void *arg)
{
int stat;
for (;;) {
assert(pid == wait(&stat));
assert(WIFSTOPPED(stat));
if (WSTOPSIG(stat) == SIGHUP)
continue;
assert(WSTOPSIG(stat) == SIGCONT);
printf("ERR! extra/wrong report:%x\n", stat);
}
}
int main(void)
{
pthread_t thread;
pid = fork();
if (!pid) {
assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0);
for (;;)
kill(getpid(), SIGHUP);
}
assert(pthread_create(&thread, NULL, waiter, NULL) == 0);
for (;;)
ptrace(PTRACE_CONT, pid, 0, SIGCONT);
return 0;
}
Note for stable: the bug is very old, but without 9899d11f65 "ptrace:
ensure arch_ptrace/ptrace_request can never race with SIGKILL" the fix
should use lock_task_sighand(child).
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Pavel Labath <labath@google.com>
Tested-by: Pavel Labath <labath@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The current smp_function_call code suffers a number of problems, most
notably smp_call_function_single_async() is broken.
The problem is that flush_smp_call_function_queue() does csd_unlock()
_after_ calling csd->func(). This means that a caller cannot properly
synchronize the csd usage as it has to.
Change the code to release the csd before calling ->func() for the
async case, and put a WARN_ON_ONCE(csd->flags & CSD_FLAG_LOCK) in
smp_call_function_single_async() to warn us of improper serialization,
because any waiting there can results in deadlocks when called with
IRQs disabled.
Rename the (currently) unused WAIT flag to SYNCHRONOUS and (re)use it
such that we know what to do in flush_smp_call_function_queue().
Rework csd_{,un}lock() to use smp_load_acquire() / smp_store_release()
to avoid some full barriers while more clearly providing lock
semantics.
Finally move the csd maintenance out of generic_exec_single() into its
callers for clearer code.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Added changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Rafael David Tinoco <inaddy@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CA+55aFz492bzLFhdbKN-Hygjcreup7CjMEYk3nTSfRWjppz-OA@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
During sysrq's show-held-locks command it is possible that
hlock_class() returns NULL for a given lock. The result is then (after
the warning):
|BUG: unable to handle kernel NULL pointer dereference at 0000001c
|IP: [<c1088145>] get_usage_chars+0x5/0x100
|Call Trace:
| [<c1088263>] print_lock_name+0x23/0x60
| [<c1576b57>] print_lock+0x5d/0x7e
| [<c1088314>] lockdep_print_held_locks+0x74/0xe0
| [<c1088652>] debug_show_all_locks+0x132/0x1b0
| [<c1315c48>] sysrq_handle_showlocks+0x8/0x10
This *might* happen because the thread on the other CPU drops the lock
after we are looking ->lockdep_depth and ->held_locks points no longer
to a lock that is held.
The fix here is to simply ignore it and continue.
Reported-by: Andreas Messerschmid <andreas@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1.
first bug is a silly mistake. It broke tracing examples and prevented
simple bpf programs from loading.
In the following code:
if (insn->imm == 0 && BPF_SIZE(insn->code) == BPF_W) {
} else if (...) {
// this part should have been executed when
// insn->code == BPF_W and insn->imm != 0
}
Obviously it's not doing that. So simple instructions like:
r2 = *(u64 *)(r1 + 8)
will be rejected. Note the comments in the code around these branches
were and still valid and indicate the true intent.
Replace it with:
if (BPF_SIZE(insn->code) != BPF_W)
continue;
if (insn->imm == 0) {
} else if (...) {
// now this code will be executed when
// insn->code == BPF_W and insn->imm != 0
}
2.
second bug is more subtle.
If malicious code is using the same dest register as source register,
the checks designed to prevent the same instruction to be used with different
pointer types will fail to trigger, since we were assigning src_reg_type
when it was already overwritten by check_mem_access().
The fix is trivial. Just move line:
src_reg_type = regs[insn->src_reg].type;
before check_mem_access().
Add new 'access skb fields bad4' test to check this case.
Fixes: 9bac3d6d54 ("bpf: allow extended BPF programs access skb fields")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to missing bounds check the DAG pass of the BPF verifier can corrupt
the memory which can cause random crashes during program loading:
[8.449451] BUG: unable to handle kernel paging request at ffffffffffffffff
[8.451293] IP: [<ffffffff811de33d>] kmem_cache_alloc_trace+0x8d/0x2f0
[8.452329] Oops: 0000 [#1] SMP
[8.452329] Call Trace:
[8.452329] [<ffffffff8116cc82>] bpf_check+0x852/0x2000
[8.452329] [<ffffffff8116b7e4>] bpf_prog_load+0x1e4/0x310
[8.452329] [<ffffffff811b190f>] ? might_fault+0x5f/0xb0
[8.452329] [<ffffffff8116c206>] SyS_bpf+0x806/0xa30
Fixes: f1bca824da ("bpf: add search pruning optimization to verifier")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a problem that trace events are not properly enabled with
boot cmdline. The problem is that if we pass "trace_event=kmem:mm_page_alloc"
to the boot cmdline, it enables all kmem trace events, and not just
the page_alloc event.
This is caused by the parsing mechanism. When we parse the cmdline, the buffer
contents is modified due to tokenization. And, if we use this buffer
again, we will get the wrong result.
Unfortunately, this buffer is be accessed three times to set trace events
properly at boot time. So, we need to handle this situation.
There is already code handling ",", but we need another for ":".
This patch adds it.
Link: http://lkml.kernel.org/r/1429159484-22977-1-git-send-email-iamjoonsoo.kim@lge.com
Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
[ added missing return ret; ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Merge second patchbomb from Andrew Morton:
- the rest of MM
- various misc bits
- add ability to run /sbin/reboot at reboot time
- printk/vsprintf changes
- fiddle with seq_printf() return value
* akpm: (114 commits)
parisc: remove use of seq_printf return value
lru_cache: remove use of seq_printf return value
tracing: remove use of seq_printf return value
cgroup: remove use of seq_printf return value
proc: remove use of seq_printf return value
s390: remove use of seq_printf return value
cris fasttimer: remove use of seq_printf return value
cris: remove use of seq_printf return value
openrisc: remove use of seq_printf return value
ARM: plat-pxa: remove use of seq_printf return value
nios2: cpuinfo: remove use of seq_printf return value
microblaze: mb: remove use of seq_printf return value
ipc: remove use of seq_printf return value
rtc: remove use of seq_printf return value
power: wakeup: remove use of seq_printf return value
x86: mtrr: if: remove use of seq_printf return value
linux/bitmap.h: improve BITMAP_{LAST,FIRST}_WORD_MASK
MAINTAINERS: CREDITS: remove Stefano Brivio from B43
.mailmap: add Ricardo Ribalda
CREDITS: add Ricardo Ribalda Delgado
...
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.
See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
Miscellanea:
o Remove unused return value from trace_lookup_stack
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The seq_printf return value, because it's frequently misused,
will eventually be converted to void.
See: commit 1f33c41c03 ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel has orderly_poweroff which allows the kernel to initiate a
graceful shutdown of userspace, by running /sbin/poweroff. This adds
orderly_reboot that will cause userspace to shut itself down by calling
/sbin/reboot.
This will be used for shutdown initiated by a system controller on
platforms that do not use ACPI.
orderly_reboot() should be used when the system wants to allow userspace
to gracefully shut itself down. For cases where the system may imminently
catch on fire, the existing emergency_restart() provides an immediate
reboot without involving userspace.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In check_hung_uninterruptible_tasks() avoid the use of deprecated
while_each_thread().
The "max_count" logic will prevent a livelock - see commit 0c740d0a
("introduce for_each_thread() to replace the buggy while_each_thread()").
Having said this let's use for_each_process_thread().
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dave Wysochanski <dwysocha@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All users of __check_region(), check_region(), and check_mem_region() are
gone. We got rid of the last user in v4.0-rc1. Remove them.
bloat-o-meter on x86_64 shows:
add/remove: 0/3 grow/shrink: 0/0 up/down: 0/-102 (-102)
function old new delta
__kstrtab___check_region 15 - -15
__ksymtab___check_region 16 - -16
__check_region 71 - -71
Signed-off-by: Jakub Sitnicki <jsitnicki@gmail.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are a lot of embedded systems that run most or all of their
functionality in init, running as root:root. For these systems,
supporting multiple users is not necessary.
This patch adds a new symbol, CONFIG_MULTIUSER, that makes support for
non-root users, non-root groups, and capabilities optional. It is enabled
under CONFIG_EXPERT menu.
When this symbol is not defined, UID and GID are zero in any possible case
and processes always have all capabilities.
The following syscalls are compiled out: setuid, setregid, setgid,
setreuid, setresuid, getresuid, setresgid, getresgid, setgroups,
getgroups, setfsuid, setfsgid, capget, capset.
Also, groups.c is compiled out completely.
In kernel/capability.c, capable function was moved in order to avoid
adding two ifdef blocks.
This change saves about 25 KB on a defconfig build. The most minimal
kernels have total text sizes in the high hundreds of kB rather than
low MB. (The 25k goes down a bit with allnoconfig, but not that much.
The kernel was booted in Qemu. All the common functionalities work.
Adding users/groups is not possible, failing with -ENOSYS.
Bloat-o-meter output:
add/remove: 7/87 grow/shrink: 19/397 up/down: 1675/-26325 (-24650)
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Iulia Manda <iulia.manda21@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, pages which are marked as unevictable are protected from
compaction, but not from other types of migration. The POSIX real time
extension explicitly states that mlock() will prevent a major page
fault, but the spirit of this is that mlock() should give a process the
ability to control sources of latency, including minor page faults.
However, the mlock manpage only explicitly says that a locked page will
not be written to swap and this can cause some confusion. The
compaction code today does not give a developer who wants to avoid swap
but wants to have large contiguous areas available any method to achieve
this state. This patch introduces a sysctl for controlling compaction
behavior with respect to the unevictable lru. Users who demand no page
faults after a page is present can set compact_unevictable_allowed to 0
and users who need the large contiguous areas can enable compaction on
locked memory by leaving the default value of 1.
To illustrate this problem I wrote a quick test program that mmaps a
large number of 1MB files filled with random data. These maps are
created locked and read only. Then every other mmap is unmapped and I
attempt to allocate huge pages to the static huge page pool. When the
compact_unevictable_allowed sysctl is 0, I cannot allocate hugepages
after fragmenting memory. When the value is set to 1, allocations
succeed.
Signed-off-by: Eric B Munson <emunson@akamai.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mem_cgroup_lookup() is a wrapper around mem_cgroup_from_id(), which
checks that id != 0 before issuing the function call. Today, there is
no point in this additional check apart from optimization, because there
is no css with id <= 0, so that css_from_id, called by
mem_cgroup_from_id, will return NULL for any id <= 0.
Since mem_cgroup_from_id is only called from mem_cgroup_lookup, let us
zap mem_cgroup_lookup, substituting calls to it with mem_cgroup_from_id
and moving the check if id > 0 to css_from_id.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Lai Jiangshan
Chen Hanxiao
Gong Zhaogang
Frederic Weisbecker
Linus Torvalds
Steven Rostedt (Red Hat)
Davidlohr Bueso
Andrey Ryabinin
Heinrich Schuchardt
Konstantin Khlebnikov
Jean Delvare
Michal Hocko
Vladimir Davydov
Oleg Nesterov
Peter Zijlstra
Alexei Starovoitov
Joonsoo Kim
Rabin Vincent
Joe Perches
Joel Stanley
Aaron Tomlin
Jakub Sitnicki
Iulia Manda
Eric B Munson