When using the "compat" APIs, architectures will generally want to
be able to make direct syscalls to msgsnd(), shmctl(), etc., and
in the kernel we would want them to be handled directly by
compat_sys_xxx() functions, as is true for other compat syscalls.
However, for historical reasons, several of the existing compat IPC
syscalls do not do this. semctl() expects a pointer to the fourth
argument, instead of the fourth argument itself. msgsnd(), msgrcv()
and shmat() expect arguments in different order.
This change adds an ARCH_WANT_OLD_COMPAT_IPC config option that can be
set to preserve this behavior for ports that use it (x86, sparc, powerpc,
s390, and mips). No actual semantics are changed for those architectures,
and there is only a minimal amount of code refactoring in ipc/compat.c.
Newer architectures like tile (and perhaps future architectures such
as arm64 and unicore64) should not select this option, and thus can
avoid having any IPC-specific code at all in their architecture-specific
compat layer. In the same vein, if this option is not selected, IPC_64
mode is assumed, since that's what the <asm-generic> headers expect.
The workaround code in "tile" for msgsnd() and msgrcv() is removed
with this change; it also fixes the bug that shmat() and semctl() were
not being properly handled.
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Adding struct _sigchld_x32 caused a misalignment cascade in struct
siginfo, because union _sifields is located on an 4-byte boundary
(8-byte misaligned.)
Adding new fields that are 8-byte aligned caused the intermediate
structures to also be aligned to 8 bytes, thereby adding padding in
unexpected places.
Thus, change s64 to compat_s64 here, which makes it "misaligned on
paper". In reality these fields *are* actually aligned (there are 3
preceeding ints outside the union and 3 inside struct _sigchld_x32),
but because of the intervening union and struct it is not possible for
gcc to avoid padding without breaking the ABI.
Reported-and-tested-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
Move APIC ID validity check into platform APIC code, so it can
be overridden when needed. For NumaChip systems, always trust
MADT, as it's constructed with high APIC IDs.
Behaviour verifies on standard x86 systems and on NumaChip
systems with this, and compile-tested with allyesconfig.
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Reviewed-by: Steffen Persvold <sp@numascale.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/1331709454-27966-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Merge tag 'v3.3-rc7' into x86/mce
Merge reason: Update from an ancient -rc1 base to an almost-final stable kernel.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix a stray ! which flipped the sense if we were generating a signal
frame for ia32 vs. x32.
Introduced in:
e7084fd5 x32: Switch to a 64-bit clock_t
Reported-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Gregory M. Lueck <gregory.m.lueck@intel.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
is_ia32_task() is useful even in !CONFIG_COMPAT cases - utrace will
use it for example. Hence move it to a more generic file: asm/thread_info.h
Also now is_ia32_task() returns true if CONFIG_X86_32 is defined.
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120313140303.17134.1401.sendpatchset@srdronam.in.ibm.com
[ Performed minor cleanup ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When a machine boots up, the TSC generally gets reset. However,
when kexec is used to boot into a kernel, the TSC value would be
carried over from the previous kernel. The computation of
cycns_offset in set_cyc2ns_scale is prone to an overflow, if the
machine has been up more than 208 days prior to the kexec. The
overflow happens when we multiply *scale, even though there is
enough room to store the final answer.
We fix this issue by decomposing tsc_now into the quotient and
remainder of division by CYC2NS_SCALE_FACTOR and then performing
the multiplication separately on the two components.
Refactor code to share the calculation with the previous
fix in __cycles_2_ns().
Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Turner <pjt@google.com>
Cc: john stultz <johnstul@us.ibm.com>
Link: http://lkml.kernel.org/r/20120310004027.19291.88460.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There are precedences of trap number being referred to as
trap_nr. However thread struct refers trap number as trap_no.
Change it to trap_nr.
Also use enum instead of left-over literals for trap values.
This is pure cleanup, no functional change intended.
Suggested-by: Ingo Molnar <mingo@eltu.hu>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@linux.vnet.ibm.com>
Cc: Linux-mm <linux-mm@kvack.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20120312092555.5379.942.sendpatchset@srdronam.in.ibm.com
[ Fixed the math-emu build ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With the recent changes to clear_IO_APIC_pin() which tries to
clear remoteIRR bit explicitly, some of the users started to see
"Unable to reset IRR for apic .." messages.
Close look shows that these are related to bogus IO-APIC entries
which return's all 1's for their io-apic registers. And the
above mentioned error messages are benign. But kernel should
have ignored such io-apic's in the first place.
Check if register 0, 1, 2 of the listed io-apic are all 1's and
ignore such io-apic.
Reported-by: Álvaro Castillo <midgoon@gmail.com>
Tested-by: Jon Dufresne <jon@jondufresne.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: yinghai@kernel.org
Cc: kernel-team@fedoraproject.org
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1331577393.31585.94.camel@sbsiddha-desk.sc.intel.com
[ Performed minor cleanup of affected code. ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I got somewhat tired of having to decode hex numbers..
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Link: http://lkml.kernel.org/n/tip-0vsy1sgywc4uar3mu1szm0rg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stepan found:
CPU0 CPUn
_cpu_up()
__cpu_up()
boostrap()
notify_cpu_starting()
set_cpu_online()
while (!cpu_active())
cpu_relax()
<PREEMPT-out>
smp_call_function(.wait=1)
/* we find cpu_online() is true */
arch_send_call_function_ipi_mask()
/* wait-forever-more */
<PREEMPT-in>
local_irq_enable()
cpu_notify(CPU_ONLINE)
sched_cpu_active()
set_cpu_active()
Now the purpose of cpu_active is mostly with bringing down a cpu, where
we mark it !active to avoid the load-balancer from moving tasks to it
while we tear down the cpu. This is required because we only update the
sched_domain tree after we brought the cpu-down. And this is needed so
that some tasks can still run while we bring it down, we just don't want
new tasks to appear.
On cpu-up however the sched_domain tree doesn't yet include the new cpu,
so its invisible to the load-balancer, regardless of the active state.
So instead of setting the active state after we boot the new cpu (and
consequently having to wait for it before enabling interrupts) set the
cpu active before we set it online and avoid the whole mess.
Reported-by: Stepan Moskovchenko <stepanm@codeaurora.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1323965362.18942.71.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Merge tag 'v3.3-rc7' into gpio/next
Linux 3.3-rc7. Merged into the gpio branch to pick up gpio bugfixes already
in mainline before queueing up move v3.4 patches
For the hypervisor to take advantage of the MWAIT support it needs
to extract from the ACPI _CST the register address. But the
hypervisor does not have the support to parse DSDT so it relies on
the initial domain (dom0) to parse the ACPI Power Management information
and push it up to the hypervisor. The pushing of the data is done
by the processor_harveset_xen module which parses the information that
the ACPI parser has graciously exposed in 'struct acpi_processor'.
For the ACPI parser to also expose the Cx states for MWAIT, we need
to expose the MWAIT capability (leaf 1). Furthermore we also need to
expose the MWAIT_LEAF capability (leaf 5) for cstate.c to properly
function.
The hypervisor could expose these flags when it traps the XEN_EMULATE_PREFIX
operations, but it can't do it since it needs to be backwards compatible.
Instead we choose to use the native CPUID to figure out if the MWAIT
capability exists and use the XEN_SET_PDC query hypercall to figure out
if the hypervisor wants us to expose the MWAIT_LEAF capability or not.
Note: The XEN_SET_PDC query was implemented in c/s 23783:
"ACPI: add _PDC input override mechanism".
With this in place, instead of
C3 ACPI IOPORT 415
we get now
C3:ACPI FFH INTEL MWAIT 0x20
Note: The cpu_idle which would be calling the mwait variants for idling
never gets set b/c we set the default pm_idle to be the hypercall variant.
Acked-by: Jan Beulich <JBeulich@suse.com>
[v2: Fix missing header file include and #ifdef]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We needed that call in the past to force the kernel to use
default_idle (which called safe_halt, which called xen_safe_halt).
But set_pm_idle_to_default() does now that, so there is no need
to use this boot option operand.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
We need to merge this ahead of some of the cleanup because a lot of needed
cleanup spans both new and old chips. If we try and clean up and the merge
we end up fighting ourselves.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[With a load of the cleanup stuff folded in, register stuff reworked sanely]
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The traps are referred to by their numbers and it can be difficult to
understand them while reading the code without context. This patch adds
enumeration of the trap numbers and replaces the numbers with the correct
enum for x86.
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20120310000710.GA32667@www.outflux.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Commit f0fbf0abc0 ("x86: integrate delay functions") converted
delay_tsc() into a random delay generator for 64 bit. The reason is
that it merged the mostly identical versions of delay_32.c and
delay_64.c. Though the subtle difference of the result was:
static void delay_tsc(unsigned long loops)
{
- unsigned bclock, now;
+ unsigned long bclock, now;
Now the function uses rdtscl() which returns the lower 32bit of the
TSC. On 32bit that's not problematic as unsigned long is 32bit. On 64
bit this fails when the lower 32bit are close to wrap around when
bclock is read, because the following check
if ((now - bclock) >= loops)
break;
evaluated to true on 64bit for e.g. bclock = 0xffffffff and now = 0
because the unsigned long (now - bclock) of these values results in
0xffffffff00000001 which is definitely larger than the loops
value. That explains Tvortkos observation:
"Because I am seeing udelay(500) (_occasionally_) being short, and
that by delaying for some duration between 0us (yep) and 491us."
Make those variables explicitely u32 again, so this works for both 32
and 64 bit.
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@onelan.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org # >= 2.6.27
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ok, this is hacky, and only works on little-endian machines with goo
unaligned handling. And even then only with CONFIG_DEBUG_PAGEALLOC
disabled, since it can access up to 7 bytes after the pathname.
But it runs like a bat out of hell.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The code which checks whether to inject a pagefault to L1 or L2 (in
nested VMX) was wrong, incorrect in how it checked the PF_VECTOR bit.
Thanks to Dan Carpenter for spotting this.
Signed-off-by: Nadav Har'El <nyh@il.ibm.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When CPUID Fn8000_0001_EAX reports 0x00100f22 Windows 7 x64 guest
tries to set bit 3 in MSRC001_0015 in nt!KiDisableCacheErrataSource
and fails. This patch will ignore this step and allow things to move
on without having to fake CPUID value.
Signed-off-by: Nicolae Mogoreanu <mogoreanu@gmail.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The reset_rsvds_bits_mask() function can use the guest walker's root level
number instead of using a separate 'level' variable.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently pmu emulation emulates fixed counter 2 as bus cycles
architectural counter, but since commit 9c1497ea59 perf has
pseudo encoding for it. Use it.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If eventsel has EDGE, INV or CMASK set we should create raw counter for
it, but the check is done on a wrong variable. Fix it.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Print warning once if pin control bit is set in eventsel msr since
emulation does not support it yet.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Shared MSRs (MSR_*STAR and related) are stored in both vmx->guest_msrs
and in the CPU registers, but vmx_set_msr() only updated memory. Prior
to 46199f33c2, this didn't matter, since we called vmx_load_host_state(),
which scheduled a vmx_save_host_state(), which re-synchronized the CPU
state, but now we don't, so the CPU state will not be synchronized until
the next exit to host userspace. This mostly affects nested vmx workloads,
which play with these MSRs a lot.
Fix by loading the MSR eagerly.
Signed-off-by: Avi Kivity <avi@redhat.com>
PCI 2.3 allows to generically disable IRQ sources at device level. This
enables us to share legacy IRQs of such devices with other host devices
when passing them to a guest.
The new IRQ sharing feature introduced here is optional, user space has
to request it explicitly. Moreover, user space can inform us about its
view of PCI_COMMAND_INTX_DISABLE so that we can avoid unmasking the
interrupt and signaling it if the guest masked it via the virtualized
PCI config space.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If some vcpus are created before KVM_CREATE_IRQCHIP, then
irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading
to potential NULL pointer dereferences.
Fix by:
- ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called
- ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP
This is somewhat long winded because vcpu->arch.apic is created without
kvm->lock held.
Based on earlier patch by Michael Ellerman.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Avi Kivity <avi@redhat.com>
Task switches can switch between Protected Mode and VM86. The current
mode must be updated during the task switch emulation so that the new
segment selectors are interpreted correctly.
In order to let privilege checks succeed, rflags needs to be updated in
the vcpu struct as this causes a CPL update.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Keep CPL at 0 in real mode and at 3 in VM86. In protected/long mode, use
RPL rather than DPL of the code segment.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Setting the segment DPL to 0 for at least the VM86 code segment makes
the VM entry fail on VMX.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently, all task switches check privileges against the DPL of the
TSS. This is only correct for jmp/call to a TSS. If a task gate is used,
the DPL of this take gate is used for the check instead. Exceptions,
external interrupts and iret shouldn't perform any check.
[avi: kill kvm-kmod remnants]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Some members of kvm_memory_slot are not used by every architecture.
This patch is the first step to make this difference clear by
introducing kvm_memory_slot::arch; lpage_info is moved into it.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch cleans up the code and removes the "(void)level;" warning
suppressor.
Note that we can also use this for PT_PAGE_TABLE_LEVEL to treat every
level uniformly later.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch fixes a race introduced by:
commit 95d4c16ce7
KVM: Optimize dirty logging by rmap_write_protect()
During protecting pages for dirty logging, other threads may also try
to protect a page in mmu_sync_children() or kvm_mmu_get_page().
In such a case, because get_dirty_log releases mmu_lock before flushing
TLB's, the following race condition can happen:
A (get_dirty_log) B (another thread)
lock(mmu_lock)
clear pte.w
unlock(mmu_lock)
lock(mmu_lock)
pte.w is already cleared
unlock(mmu_lock)
skip TLB flush
return
...
TLB flush
Though thread B assumes the page has already been protected when it
returns, the remaining TLB entry will break that assumption.
This patch fixes this problem by making get_dirty_log hold the mmu_lock
until it flushes the TLB's.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
yield_on_hlt was introduced for CPU bandwidth capping. Now it is
redundant with CFS hardlimit.
yield_on_hlt also complicates the scenario in paravirtual environment,
that needs to trap halt. for e.g. paravirtualized ticket spinlocks.
Acked-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This allows us to track the original nanosecond and counter values
at each phase of TSC writing by the guest. This gets us perfect
offset matching for stable TSC systems, and perfect software
computed TSC matching for machines with unstable TSC.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
During a host suspend, TSC may go backwards, which KVM interprets
as an unstable TSC. Technically, KVM should not be marking the
TSC unstable, which causes the TSC clocksource to go bad, but we
need to be adjusting the TSC offsets in such a case.
Dealing with this issue is a little tricky as the only place we
can reliably do it is before much of the timekeeping infrastructure
is up and running. On top of this, we are not in a KVM thread
context, so we may not be able to safely access VCPU fields.
Instead, we compute our best known hardware offset at power-up and
stash it to be applied to all VCPUs when they actually start running.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Redefine the API to take a parameter indicating whether an
adjustment is in host or guest cycles.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The variable last_host_tsc was removed from upstream code. I am adding
it back for two reasons. First, it is unnecessary to use guest TSC
computation to conclude information about the host TSC. The guest may
set the TSC backwards (this case handled by the previous patch), but
the computation of guest TSC (and fetching an MSR) is significanlty more
work and complexity than simply reading the hardware counter. In addition,
we don't actually need the guest TSC for any part of the computation,
by always recomputing the offset, we can eliminate the need to deal with
the current offset and any scaling factors that may apply.
The second reason is that later on, we are going to be using the host
TSC value to restore TSC offsets after a host S4 suspend, so we need to
be reading the host values, not the guest values here.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The variable last_guest_tsc was being used as an ad-hoc indicator
that guest TSC has been initialized and recorded correctly. However,
it may not have been, it could be that guest TSC has been set to some
large value, the back to a small value (by, say, a software reboot).
This defeats the logic and causes KVM to falsely assume that the
guest TSC has gone backwards, marking the host TSC unstable, which
is undesirable behavior.
In addition, rather than try to compute an offset adjustment for the
TSC on unstable platforms, just recompute the whole offset. This
allows us to get rid of one callsite for adjust_tsc_offset, which
is problematic because the units it takes are in guest units, but
here, the computation was originally being done in host units.
Doing this, and also recording last_guest_tsc when the TSC is written
allow us to remove the tricky logic which depended on last_guest_tsc
being zero to indicate a reset of uninitialized value.
Instead, we now have the guarantee that the guest TSC offset is
always at least something which will get us last_guest_tsc.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently, when the TSC is written by the guest, the variable
ns is updated to force the current write to appear to have taken
place at the time of the first write in this sync phase. This
leaves a cliff at the end of the match window where updates will
fall of the end. There are two scenarios where this can be a
problem in practe - first, on a system with a large number of
VCPUs, the sync period may last for an extended period of time.
The second way this can happen is if the VM reboots very rapidly
and we catch a VCPU TSC synchronization just around the edge.
We may be unaware of the reboot, and thus the first VCPU might
synchronize with an old set of the timer (at, say 0.97 seconds
ago, when first powered on). The second VCPU can come in 0.04
seconds later to try to synchronize, but it misses the window
because it is just over the threshold.
Instead, stop doing this artificial setback of the ns variable
and just update it with every write of the TSC.
It may be observed that doing so causes values computed by
compute_guest_tsc to diverge slightly across CPUs - note that
the last_tsc_ns and last_tsc_write variable are used here, and
now they last_tsc_ns will be different for each VCPU, reflecting
the actual time of the update.
However, compute_guest_tsc is used only for guests which already
have TSC stability issues, and further, note that the previous
patch has caused last_tsc_write to be incremented by the difference
in nanoseconds, converted back into guest cycles. As such, only
boundary rounding errors should be visible, which given the
resolution in nanoseconds, is going to only be a few cycles and
only visible in cross-CPU consistency tests. The problem can be
fixed by adding a new set of variables to track the start offset
and start write value for the current sync cycle.
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There are a few improvements that can be made to the TSC offset
matching code. First, we don't need to call the 128-bit multiply
(especially on a constant number), the code works much nicer to
do computation in nanosecond units.
Second, the way everything is setup with software TSC rate scaling,
we currently have per-cpu rates. Obviously this isn't too desirable
to use in practice, but if for some reason we do change the rate of
all VCPUs at runtime, then reset the TSCs, we will only want to
match offsets for VCPUs running at the same rate.
Finally, for the case where we have an unstable host TSC, but
rate scaling is being done in hardware, we should call the platform
code to compute the TSC offset, so the math is reorganized to recompute
the base instead, then transform the base into an offset using the
existing API.
[avi: fix 64-bit division on i386]
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
KVM: Fix 64-bit division in kvm_write_tsc()
Breaks i386 build.
Signed-off-by: Avi Kivity <avi@redhat.com>
This requires some restructuring; rather than use 'virtual_tsc_khz'
to indicate whether hardware rate scaling is in effect, we consider
each VCPU to always have a virtual TSC rate. Instead, there is new
logic above the vendor-specific hardware scaling that decides whether
it is even necessary to use and updates all rate variables used by
common code. This means we can simply query the virtual rate at
any point, which is needed for software rate scaling.
There is also now a threshold added to the TSC rate scaling; minor
differences and variations of measured TSC rate can accidentally
provoke rate scaling to be used when it is not needed. Instead,
we have a tolerance variable called tsc_tolerance_ppm, which is
the maximum variation from user requested rate at which scaling
will be used. The default is 250ppm, which is the half the
threshold for NTP adjustment, allowing for some hardware variation.
In the event that hardware rate scaling is not available, we can
kludge a bit by forcing TSC catchup to turn on when a faster than
hardware speed has been requested, but there is nothing available
yet for the reverse case; this requires a trap and emulate software
implementation for RDTSC, which is still forthcoming.
[avi: fix 64-bit division on i386]
Signed-off-by: Zachary Amsden <zamsden@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
While for a user mode register dump it may be reasonable to skip
those (albeit x86-64 doesn't do so), for kernel mode dumps these
should be printed to make sure all information possibly
necessary for analysis is available.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/4F58889202000078000770E7@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Building in support for either of these CPUs is pointless when
e.g. M686 was selected (since such a kernel would use cmov
instructions, which aren't available on these older CPUs).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/4F58875A02000078000770E0@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
It turns out that test-compiling this file on x86-64 doesn't really
help, because much of it is x86-32-specific. And so I hadn't noticed
the slightly over-eager removal of the 'r' from 'addr' variable despite
thinking I had tested it.
Signed-off-by: Linus "oopsie" Torvalds <torvalds@linux-foundation.org>
Several users of "find_vma_prev()" were not in fact interested in the
previous vma if there was no primary vma to be found either. And in
those cases, we're much better off just using the regular "find_vma()",
and then "prev" can be looked up by just checking vma->vm_prev.
The find_vma_prev() semantics are fairly subtle (see Mikulas' recent
commit 83cd904d271b: "mm: fix find_vma_prev"), and the whole "return
prev by reference" means that it generates worse code too.
Thus this "let's avoid using this inconvenient and clearly too subtle
interface when we don't really have to" patch.
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Like most systems, OLPC's ACPI LID switch wakes up the system
when the lid is opened, but not when it is closed.
Under OLPC's opportunistic suspend model, the lid may be closed
while the system was oportunistically suspended with the screen
running. In this event, we want to wake up to turn the screen
off.
Enable control of normal ACPI wakeups through lid close events
through a new sysfs attribute "lid_wake_on_closed". When set,
and when LID wakeups are enabled through ACPI, the system will
wake up on both open and close lid events.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Cc: Andres Salomon <dilinger@queued.net>
Cc: Matthew Garrett <mjg@redhat.com>
[ Fixed sscanf checking]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-bgt8hxu2wwe0x5p8edhogtf7@git.kernel.org
[ Did very minor readability tweaks ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix a bug in kprobes which can modify kernel code
permanently at run-time. In the result, kernel can
crash when it executes the modified code.
This bug can happen when we put two probes enough near
and the first probe is optimized. When the second probe
is set up, it copies a byte which is already modified
by the first probe, and executes it when the probe is hit.
Even worse, the first probe and the second probe are removed
respectively, the second probe writes back the copied
(modified) instruction.
To fix this bug, kprobes always recovers the original
code and copies the first byte from recovered instruction.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: systemtap@sourceware.org
Cc: anderson@redhat.com
Link: http://lkml.kernel.org/r/20120305133215.5982.31991.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Current probed-instruction recovery expects that only breakpoint
instruction modifies instruction. However, since kprobes jump
optimization can replace original instructions with a jump,
that expectation is not enough. And it may cause instruction
decoding failure on the function where an optimized probe
already exists.
This bug can reproduce easily as below:
1) find a target function address (any kprobe-able function is OK)
$ grep __secure_computing /proc/kallsyms
ffffffff810c19d0 T __secure_computing
2) decode the function
$ objdump -d vmlinux --start-address=0xffffffff810c19d0 --stop-address=0xffffffff810c19eb
vmlinux: file format elf64-x86-64
Disassembly of section .text:
ffffffff810c19d0 <__secure_computing>:
ffffffff810c19d0: 55 push %rbp
ffffffff810c19d1: 48 89 e5 mov %rsp,%rbp
ffffffff810c19d4: e8 67 8f 72 00 callq
ffffffff817ea940 <mcount>
ffffffff810c19d9: 65 48 8b 04 25 40 b8 mov %gs:0xb840,%rax
ffffffff810c19e0: 00 00
ffffffff810c19e2: 83 b8 88 05 00 00 01 cmpl $0x1,0x588(%rax)
ffffffff810c19e9: 74 05 je ffffffff810c19f0 <__secure_computing+0x20>
3) put a kprobe-event at an optimize-able place, where no
call/jump places within the 5 bytes.
$ su -
# cd /sys/kernel/debug/tracing
# echo p __secure_computing+0x9 > kprobe_events
4) enable it and check it is optimized.
# echo 1 > events/kprobes/p___secure_computing_9/enable
# cat ../kprobes/list
ffffffff810c19d9 k __secure_computing+0x9 [OPTIMIZED]
5) put another kprobe on an instruction after previous probe in
the same function.
# echo p __secure_computing+0x12 >> kprobe_events
bash: echo: write error: Invalid argument
# dmesg | tail -n 1
[ 1666.500016] Probing address(0xffffffff810c19e2) is not an instruction boundary.
6) however, if the kprobes optimization is disabled, it works.
# echo 0 > /proc/sys/debug/kprobes-optimization
# cat ../kprobes/list
ffffffff810c19d9 k __secure_computing+0x9
# echo p __secure_computing+0x12 >> kprobe_events
(no error)
This is because kprobes doesn't recover the instruction
which is overwritten with a relative jump by another kprobe
when finding instruction boundary.
It only recovers the breakpoint instruction.
This patch fixes kprobes to recover such instructions.
With this fix:
# echo p __secure_computing+0x9 > kprobe_events
# echo 1 > events/kprobes/p___secure_computing_9/enable
# cat ../kprobes/list
ffffffff810c1aa9 k __secure_computing+0x9 [OPTIMIZED]
# echo p __secure_computing+0x12 >> kprobe_events
# cat ../kprobes/list
ffffffff810c1aa9 k __secure_computing+0x9 [OPTIMIZED]
ffffffff810c1ab2 k __secure_computing+0x12 [DISABLED]
Changes in v4:
- Fix a bug to ensure optimized probe is really optimized
by jump.
- Remove kprobe_optready() dependency.
- Cleanup code for preparing optprobe separation.
Changes in v3:
- Fix a build error when CONFIG_OPTPROBE=n. (Thanks, Ingo!)
To fix the error, split optprobe instruction recovering
path from kprobes path.
- Cleanup comments/styles.
Changes in v2:
- Fix a bug to recover original instruction address in
RIP-relative instruction fixup.
- Moved on tip/master.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: yrl.pp-manager.tt@hitachi.com
Cc: systemtap@sourceware.org
Cc: anderson@redhat.com
Link: http://lkml.kernel.org/r/20120305133209.5982.36568.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add platform driver for the Soekris Engineering net5501 single-board
computer. Probes well-known locations in ROM for BIOS signature
to confirm correct platform. Registers 1 LED and 1 GPIO-based
button (typically used for soft reset).
Signed-off-by: Philip Prindeville <philipp@redfish-solutions.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Andres Salomon <dilinger@queued.net>
Cc: Matthew Garrett <mjg@redhat.com>
[ Removed Kconfig and Makefile detritus from drivers/leds/]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-jv5uf34996juqh5syes8mn4h@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
GPIO 24 is used in reference designs as a soft-reset button, and
the alix2 is no exception. Add it as a gpio-button.
Use symbolic values to describe BIOS addresses.
Record the model number.
Signed-off-by: Philip A. Prindeville <philipp@redfish-solutions.com>
Acked-by: Ed Wildgoose <kernel@wildgooses.com>
Acked-by: Andres Salomon <dilinger@queued.net>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-sjp6k1rjksitx1pej0c0qxd1@git.kernel.org
[ tidied up the code a bit ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
X32 ptrace is a hybrid of 64bit ptrace and compat ptrace with 32bit
address and longs. It use 64bit ptrace to access the full 64bit
registers. PTRACE_PEEKUSR and PTRACE_POKEUSR are only allowed to access
segment and debug registers. PTRACE_PEEKUSR returns the lower 32bits
and PTRACE_POKEUSR zero-extends 32bit value to 64bit. It works since
the upper 32bits of segment and debug registers of x32 process are always
zero. GDB only uses PTRACE_PEEKUSR and PTRACE_POKEUSR to access
segment and debug registers.
[ hpa: changed TIF_X32 test to use !is_ia32_task() instead, and moved
the system call number to the now-unused 521 slot. ]
Signed-off-by: "H.J. Lu" <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Roland McGrath <roland@hack.frob.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
clock_t is used mainly to give the number of jiffies a certain process
has burned. It is entirely feasible for a long-running process to
consume more than 2^32 jiffies especially in a multiprocess system.
As such, switch to a 64-bit clock_t for x32, just as we already
switched to a 64-bit time_t.
clock_t is only used in a handful of places, and as such it is really
not a very significant change. The one that has the biggest impact is
in struct siginfo, but since the *size* of struct siginfo doesn't
change (it is padded to the hilt) it is fairly easy to make this a
localized change.
This also gets rid of sys_x32_times, however since this is a pretty
late change don't compactify the system call numbers; we can reuse
system call slot 521 next time we need an x32 system call.
Reported-by: Gregory M. Lueck <gregory.m.lueck@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
Pull PCI fixes from Jesse Barnes:
"A couple of fixes for booting specific machines, and one for a minor
memory leak on pre-_CRS platforms."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
x86/PCI: do not tie MSI MS-7253 use_crs quirk to BIOS version
x86/PCI: use host bridge _CRS info on MSI MS-7253
PCI: fix memleak when ACPI _CRS is not used.
With branch stack sampling, it is possible to filter by priv levels.
In system-wide mode, that means it is possible to capture only user
level branches. The builtin SW LBR filter needs to disassemble code
based on LBR captured addresses. For that, it needs to know the task
the addresses are associated with. Because of context switches, the
content of the branch stack buffer may contain addresses from
different tasks.
We need a callback on context switch to either flush the branch stack
or save it. This patch adds a new callback in struct pmu which is called
during context switches. The callback is called only when necessary.
That is when a system-wide context has, at least, one event which
uses PERF_SAMPLE_BRANCH_STACK. The callback is never called for
per-thread context.
In this version, the Intel x86 code simply flushes (resets) the LBR
on context switches (fills it with zeroes). Those zeroed branches are
then filtered out by the SW filter.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-11-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds an internal sofware filter to complement
the (optional) LBR hardware filter.
The software filter is necessary:
- as a substitute when there is no HW LBR filter (e.g., Atom, Core)
- to complement HW LBR filter in case of errata (e.g., Nehalem/Westmere)
- to provide finer grain filtering (e.g., all processors)
Sometimes the LBR HW filter cannot distinguish between two types
of branches. For instance, to capture syscall as CALLS, it is necessary
to enable the LBR_FAR filter which will also capture JMP instructions.
Thus, a second pass is necessary to filter those out, this is what the
SW filter can do.
The SW filter is built on top of the internal x86 disassembler. It
is a best effort filter especially for user level code. It is subject
to the availability of the text page of the program.
The SW filter is enabled on all Intel processors. It is bypassed
when the user is capturing all branches at all priv levels.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-9-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch implements PERF_SAMPLE_BRANCH support for Intel
x86processors. It connects PERF_SAMPLE_BRANCH to the actual LBR.
The patch adds the hooks in the PMU irq handler to save the LBR
on counter overflow for both regular and PEBS modes.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-8-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The patch adds a restriction for Intel Atom LBR support. Only
steppings 10 (PineView) and more recent are supported. Older models
do not have a functional LBR. Their LBR does not freeze on PMU
interrupt which makes LBR unusable in the context of perf_events.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-7-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds the mappings from the generic PERF_SAMPLE_BRANCH_*
filters to the actual Intel x86LBR filters, whenever they exist.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-6-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If precise sampling is enabled on Intel x86 then perf_event uses PEBS.
To correct for the off-by-one error of PEBS, perf_event uses LBR when
precise_sample > 1.
On Intel x86 PERF_SAMPLE_BRANCH_STACK is implemented using LBR,
therefore both features must be coordinated as they may not
configure LBR the same way.
For PEBS, LBR needs to capture all branches at the priv level of
the associated event.
This patch checks that the branch type and priv level of BRANCH_STACK
is compatible with that of the PEBS LBR requirement, thereby allowing:
$ perf record -b any,u -e instructions:upp ....
But:
$ perf record -b any_call,u -e instructions:upp
Is not possible.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-5-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The Intel LBR on some recent processor is capable
of filtering branches by type. The filter is configurable
via the LBR_SELECT MSR register.
There are limitation on how this register can be used.
On Nehalem/Westmere, the LBR_SELECT is shared by the two HT threads
when HT is on. It is private to each core when HT is off.
On SandyBridge, the LBR_SELECT register is private to each thread
when HT is on. It is private to each core when HT is off.
The kernel must manage the sharing of LBR_SELECT. It allows
multiple users on the same logical CPU to use LBR_SELECT as
long as they program it with the same value. Across sibling
CPUs (HT threads), the same restriction applies on NHM/WSM.
This patch implements this sharing logic by leveraging the
mechanism put in place for managing the offcore_response
shared MSR.
We modify __intel_shared_reg_get_constraints() to cause
x86_get_event_constraint() to be called because LBR may
be associated with events that may be counter constrained.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-4-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds the LBR definitions for NHM/WSM/SNB and Core.
It also adds the definitions for the architected LBR MSR:
LBR_SELECT, LBRT_TOS.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-3-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds the ability to sample taken branches to the
perf_event interface.
The ability to capture taken branches is very useful for all
sorts of analysis. For instance, basic block profiling, call
counts, statistical call graph.
This new capability requires hardware assist and as such may
not be available on all HW platforms. On Intel x86 it is
implemented on top of the Last Branch Record (LBR) facility.
To enable taken branches sampling, the PERF_SAMPLE_BRANCH_STACK
bit must be set in attr->sample_type.
Sampled taken branches may be filtered by type and/or priv
levels.
The patch adds a new field, called branch_sample_type, to the
perf_event_attr structure. It contains a bitmask of filters
to apply to the sampled taken branches.
Filters may be implemented in HW. If the HW filter does not exist
or is not good enough, some arch may also implement a SW filter.
The following generic filters are currently defined:
- PERF_SAMPLE_USER
only branches whose targets are at the user level
- PERF_SAMPLE_KERNEL
only branches whose targets are at the kernel level
- PERF_SAMPLE_HV
only branches whose targets are at the hypervisor level
- PERF_SAMPLE_ANY
any type of branches (subject to priv levels filters)
- PERF_SAMPLE_ANY_CALL
any call branches (may incl. syscall on some arch)
- PERF_SAMPLE_ANY_RET
any return branches (may incl. syscall returns on some arch)
- PERF_SAMPLE_IND_CALL
indirect call branches
Obviously filter may be combined. The priv level bits are optional.
If not provided, the priv level of the associated event are used. It
is possible to collect branches at a priv level different from the
associated event. Use of kernel, hv priv levels is subject to permissions
and availability (hv).
The number of taken branch records present in each sample may vary based
on HW, the type of sampled branches, the executed code. Therefore
each sample contains the number of taken branches it contains.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1328826068-11713-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Increase recommended max vcpus from 64 to 160 (tested internally
at Red Hat).
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
When kvm guest uses kvmclock, it may hang on vcpu hot-plug.
This is caused by an overflow in pvclock_get_nsec_offset,
u64 delta = tsc - shadow->tsc_timestamp;
which in turn is caused by an undefined values from percpu
hv_clock that hasn't been initialized yet.
Uninitialized clock on being booted cpu is accessed from
start_secondary
-> smp_callin
-> smp_store_cpu_info
-> identify_secondary_cpu
-> mtrr_ap_init
-> mtrr_restore
-> stop_machine_from_inactive_cpu
-> queue_stop_cpus_work
...
-> sched_clock
-> kvm_clock_read
which is well before x86_cpuinit.setup_percpu_clockev call in
start_secondary, where percpu clock is initialized.
This patch introduces a hook that allows to setup/initialize
per_cpu clock early and avoid overflow due to reading
- undefined values
- old values if cpu was offlined and then onlined again
Another possible early user of this clock source is ftrace that
accesses it to get timestamps for ring buffer entries. So if
mtrr_ap_init is moved from identify_secondary_cpu to past
x86_cpuinit.setup_percpu_clockev in start_secondary, ftrace
may cause the same overflow/hang on cpu hot-plug anyway.
More complete description of the problem:
https://lkml.org/lkml/2012/2/2/101
Credits to Marcelo Tosatti <mtosatti@redhat.com> for hook idea.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The spec says that during initialization "The edge sense circuit is
reset which means that following initialization an interrupt request
(IR) input must make a low-to-high transition to generate an interrupt",
but currently if edge triggered interrupt is in IRR it is delivered
after i8259 initialization.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If the guest thinks it's an AMD, it will not have prepared the SYSENTER MSRs,
and if the guest executes SYSENTER in compatibility mode, it will fails.
Detect this condition and #UD instead, like the spec says.
Signed-off-by: Avi Kivity <avi@redhat.com>
If the guest programs an IPI with level=0 (de-assert) and trig_mode=0 (edge),
it is erroneously treated as INIT de-assert and ignored, but to quote the
spec: "For this delivery mode [INIT de-assert], the level flag must be set to
0 and trigger mode flag to 1."
Signed-off-by: Julian Stecklina <js@alien8.de>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Also use true instead of 1 for enabling by default.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently we treat MOVSX/MOVZX with a byte source as a byte instruction,
and change the destination operand size with a hack. Change it to be
a word instruction, so the destination receives its natural size, and
change the source to be SrcMem8.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
On some cpus the overhead for virtualization instructions is in the same
range as a system call. Having to call multiple ioctls to get set registers
will make certain userspace handled exits more expensive than necessary.
Lets provide a section in kvm_run that works as a shared save area
for guest registers.
We also provide two 64bit flags fields (architecture specific), that will
specify
1. which parts of these fields are valid.
2. which registers were modified by userspace
Each bit for these flag fields will define a group of registers (like
general purpose) or a single register.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In some cases guests should not provide workarounds for errata even when the
physical processor is affected. For example, because of erratum 400 on family
10h processors a Linux guest will read an MSR (resulting in VMEXIT) before
going to idle in order to avoid getting stuck in a non-C0 state. This is not
necessary: HLT and IO instructions are intercepted and therefore there is no
reason for erratum 400 workaround in the guest.
This patch allows us to present a guest with certain errata as fixed,
regardless of the state of actual hardware.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
We can remove the first ->nx state assignment since it is assigned afterwards anyways.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch exports the s390 SIE hardware control block to userspace
via the mapping of the vcpu file descriptor. In order to do so,
a new arch callback named kvm_arch_vcpu_fault is introduced for all
architectures. It allows to map architecture specific pages.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch introduces a new config option for user controlled kernel
virtual machines. It introduces a parameter to KVM_CREATE_VM that
allows to set bits that alter the capabilities of the newly created
virtual machine.
The parameter is passed to kvm_arch_init_vm for all architectures.
The only valid modifier bit for now is KVM_VM_S390_UCONTROL.
This requires CAP_SYS_ADMIN privileges and creates a user controlled
virtual machine on s390 architectures.
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
get_written_sptes is called twice in kvm_mmu_pte_write, one of them can be
removed
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There is only one user of it and for_each_set_bit() does the same.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently cache alignment among nodes in the kernel is still 128
bytes on x86 NUMA machines - we got that X86_INTERNODE_CACHE_SHIFT
default from old P4 processors.
But now most modern x86 CPUs use the same size: 64 bytes from L1 to
last level L3. so let's remove the incorrect setting, and directly
use the L1 cache size to do SMP cache line alignment.
This patch saves some memory space on kernel data, and it also
improves the cache locality of kernel data.
The System.map is quite different with/without this change:
before patch after patch
...
000000000000b000 d tlb_vector_| 000000000000b000 d tlb_vector
000000000000b080 d cpu_loops_p| 000000000000b040 d cpu_loops_
...
Signed-off-by: Alex Shi <alex.shi@intel.com>
Cc: asit.k.mallick@intel.com
Link: http://lkml.kernel.org/r/1330774047-18597-1-git-send-email-alex.shi@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any
other BUG variant in a static inline (i.e. not in a #define) then
that header really should be including <linux/bug.h> and not just
expecting it to be implicitly present.
We can make this change risk-free, since if the files using these
headers didn't have exposure to linux/bug.h already, they would have
been causing compile failures/warnings.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
mem_hole_size() is being called only from __init-marked functions, and as
such should be moved to .init section as well. Fixes this warning:
WARNING: vmlinux.o(.text+0x35511): Section mismatch in reference from the function mem_hole_size() to the function .init.text:absent_pages_in_range()
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1202281614450.31150@pobox.suse.cz
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
'pcibios_fwaddrmap_lookup()' is used to maintain FW-assigned BIOS BAR
values for reinstatement when normal resource assignment attempts
fail and must be called with the 'pcibios_fwaddrmap_lock' spinlock
held.
This patch adds a WARN_ON notification if the spinlock is not currently
held by the caller.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
It turned out that a performance counter on AMD does not
count at all when the GO or HO bit is set in the control
register and SVM is disabled in EFER.
This patch works around this issue by masking out the HO bit
in the performance counter control register when SVM is not
enabled.
The GO bit is not touched because it is only set when the
user wants to count in guest-mode only. So when SVM is
disabled the counter should not run at all and the
not-counting is the intended behaviour.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Avi Kivity <avi@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: stable@vger.kernel.org # v3.2
Link: http://lkml.kernel.org/r/1330523852-19566-1-git-send-email-joerg.roedel@amd.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Specify the data structures for the 64-bit ioctls with explicit sizing
and padding so that the x32 kernel will correctly use the 64-bit forms
of these ioctls. Note that these ioctls are bogus in both forms on
both 32 and 64 bits; even on 64 bits the maximum MTRR size is only 44
bits long.
Note that nothing really is supposed to use these ioctls and that the
preferred interface is text strings on /proc/mtrr, or better yet,
nothing at all (use /sys/bus/pci/devices/*/resource*_wc for write
combining; that uses PAT not MTRRs.)
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Tested-by: Nitin A. Kamble <nitin.a.kamble@intel.com>
Link: http://lkml.kernel.org/n/tip-vwvnlu3hjmtkwvij4qxtm90l@git.kernel.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Carlos was getting
WARNING: at drivers/pci/pci.c:118 pci_ioremap_bar+0x24/0x52()
when probing his sound card, and sound did not work. After adding
pci=use_crs to the kernel command line, no more trouble.
Ok, we can add a quirk. dmidecode output reveals that this is an MSI
MS-7253, for which we already have a quirk, but the short-sighted
author tied the quirk to a single BIOS version, making it not kick in
on Carlos's machine with BIOS V1.2. If a later BIOS update makes it
no longer necessary to look at the _CRS info it will still be
harmless, so let's stop trying to guess which versions have and don't
have accurate _CRS tables.
Addresses https://bugtrack.alsa-project.org/alsa-bug/view.php?id=5533
Also see <https://bugzilla.kernel.org/show_bug.cgi?id=42619>.
Reported-by: Carlos Luna <caralu74@gmail.com>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
With bug.h currently living right in linux/kernel.h there
are files that use BUG_ON and friends but are not including
the header explicitly. Fix them up so we can remove the
presence in kernel.h file.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
It would appear that we never actually generated a correct CRC when
building on a bigendian machine. Depending on the word size, we would
either generate an all-zero CRC (64-bit machine) or a byte-swapped
CRC (32-bit machine.) Fix the types used so we don't arbitrarily use
a 64-bit word to hold 32-bit numbers, and pass the CRC through
put_unaligned_le32() like all the other numbers.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Bowler <nbowler@elliptictech.com>
Link: http://lkml.kernel.org/r/20120229111322.9eb4b23ff1672e8853ad3b3b@canb.auug.org.au
We include <sys/sysmacros.h> and <asm/boot.h>, but none of those
header files actually provide anything this file needs. Furthermore,
it breaks cross-compilation, so just remove them.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Bowler <nbowler@elliptictech.com>
Link: http://lkml.kernel.org/r/20120229111322.9eb4b23ff1672e8853ad3b3b@canb.auug.org.au
Since we already have a debugreg.h header file, move the
assoc. get/set functions to it. In addition to it being the
logical home for them, it has a secondary advantage. The
functions that are moved use BUG(). So we really need to
have linux/bug.h in scope. But asm/processor.h is used about
600 times, vs. only about 15 for debugreg.h -- so adding bug.h
to the latter reduces the amount of time we'll be processing
it during a compile.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: "H. Peter Anvin" <hpa@zytor.com>
In the spirit of commit 29cf7a30f8 ("x86/PCI: use host bridge _CRS
info on ASUS M2V-MX SE"), this DMI quirk turns on "pci_use_crs" by
default on a board that needs it.
This fixes boot failures and oopses introduced in 3e3da00c01
("x86/pci: AMD one chain system to use pci read out res"). The quirk
is quite targetted (to a specific board and BIOS version) for two
reasons:
(1) to emphasize that this method of tackling the problem one quirk
at a time is a little insane
(2) to give BIOS vendors an opportunity to use simpler tables and
allow us to return to generic behavior (whatever that happens to
be) with a later BIOS update
In other words, I am not at all happy with having quirks like this.
But it is even worse for the kernel not to work out of the box on
these machines, so...
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=42619
Reported-by: Svante Signell <svante.signell@telia.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We may need to convert the endianness of the data we read from/write
to 'buf', so let's use {get,put}_unaligned_le32() to do that. Failure
to do so can result in accessing invalid memory, leading to a
segfault. Stephen Rothwell noticed this bug while cross-building an
x86_64 allmodconfig kernel on PowerPC.
We need to read from and write to 'buf' a byte at a time otherwise
it's possible we'll perform an unaligned access, which can lead to bus
errors when cross-building an x86 kernel on risc architectures.
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Nick Bowler <nbowler@elliptictech.com>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-6-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Currently tools/build has access to all the kernel headers in
$(srctree). This is unnecessary and could potentially allow
tools/build to erroneously include kernel headers when it should only
be including userspace-exported headers.
Unfortunately, mkcpustr still needs access to some of the asm kernel
headers, so explicitly special case that hostprog.
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1330436245-24875-5-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
If X32 is enabled in .config, but the binutils can't build it, issue a
warning and disable the feature rather than erroring out.
In order to support this, have CONFIG_X86_X32 be the option set in
Kconfig, and CONFIG_X86_X32_ABI be the option set by the Makefile when
it is enabled and binutils has been found to be functional.
Requested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: H. J. Lu <hjl.tools@gmail.com>
Link: http://lkml.kernel.org/r/1329696488-16970-1-git-send-email-hpa@zytor.com
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce/AMD: Fix UP build error
x86: Specify a size for the cmp in the NMI handler
x86/nmi: Test saved %cs in NMI to determine nested NMI case
x86/amd: Fix L1i and L2 cache sharing information for AMD family 15h processors
x86/microcode: Remove noisy AMD microcode warning
Commit eab9e6137f ("x86-64: Fix CFI data for interrupt frames")
introduced a DW_CFA_def_cfa_expression in the SAVE_ARGS_IRQ
macro. To later define the CFA using a simple register+offset
rule both register and offset need to be supplied. Just using
CFI_DEF_CFA_REGISTER leaves the offset undefined. So use
CFI_DEF_CFA with reg+off explicitly at the end of
common_interrupt.
Signed-off-by: Mark Wielaard <mjw@redhat.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/1330079527-30711-1-git-send-email-mjw@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
After all, this code is being run once at boot only (if
configured in at all).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/4F478C010200007800074A3D@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
converted back to WB but end up being recycled in the general memory
pool as WC.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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Merge tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Two fixes to fix a memory corruption bug when WC pages never get
converted back to WB but end up being recycled in the general memory
pool as WC.
There is a better way of fixing this, but there is not enough time to do
the full benchmarking to pick one of the right options - so picking the
one that favors stability for right now.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* tag 'stable/for-linus-fixes-3.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pat: Disable PAT support for now.
xen/setup: Remove redundant filtering of PTE masks.
task->thread.usersp is unusable immediately after a binary is exec()'d
until it undergoes a context switch cycle. The start_thread() function
called during execve() saves the stack pointer into pt_regs and into
old_rsp, but fails to record it into task->thread.usersp.
Because of this, KSTK_ESP(task) returns an incorrect value for a
64-bit program until the task is switched out and back in since
switch_to swaps %rsp values in and out into task->thread.usersp.
Signed-off-by: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com>
Link: http://lkml.kernel.org/r/1330273075-2949-1-git-send-email-siddhesh.poyarekar@gmail.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
If a process has a non-x32 ia32 personality and changes to x32, the
process would keep its TS_COMPAT flag. x32 uses the presence of the
x32 flag on a syscall to determine compat status, so make sure
TS_COMPAT is cleared.
Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Link: http://lkml.kernel.org/r/1330230338-25077-1-git-send-email-bobbypowers@gmail.com
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86 has fast unaligned accesses, so twofish-x86_64/i586 does not need to enforce
alignment.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
x86 has fast unaligned accesses, so blowfish-x86_64 does not need to enforce
alignment.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Driver name in ablk_*_init functions can be constructed runtime. Therefore
use single function ablk_init to reduce object size.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Combine all crypto_alg to be registered and use new crypto_[un]register_algs
functions. Simplifies init/exit code and reduce object size.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Combine all crypto_alg to be registered and use new crypto_[un]register_algs
functions. Simplifies init/exit code and reduce object size.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Combine all crypto_alg to be registered and use new crypto_[un]register_algs
functions. Simplifies init/exit code and reduce object size.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some of the comments for the nesting NMI algorithm were stale and
had some references to some prototypes that were first tried.
I also updated the comments to be a little easier to understand
the flow of the code. It definitely needs the documentation.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
In one case, use an address register that was computed earlier (and
with a simpler instruction), thus reducing the risk of a stall.
In the second case, eliminate a branch by using a conditional move (as
is already done in call_softirq and xen_do_hypervisor_callback).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/4F4788A50200007800074A26@nat28.tlf.novell.com
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The saving and restoring of %rdx wasn't annotated at all, and the
jumping over sections where state gets partly restored wasn't handled
either.
Further, by folding the pushing of the previous frame in repeat_nmi
into that which so far was immediately preceding restart_nmi (after
moving the restore of %rdx ahead of that, since it doesn't get used
anymore when pushing prior frames), annotations of the replicated
frame creations can be made consistent too.
v2: Fully fold repeat_nmi into the normal code flow (adding a single
redundant instruction to the "normal" code path), thus retaining
the special protection of all instructions between repeat_nmi and
end_repeat_nmi.
Link: http://lkml.kernel.org/r/4F478B630200007800074A31@nat28.tlf.novell.com
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
So here's a boot tested patch on top of Jason's series that does
all the cleanups I talked about and turns jump labels into a
more intuitive to use facility. It should also address the
various misconceptions and confusions that surround jump labels.
Typical usage scenarios:
#include <linux/static_key.h>
struct static_key key = STATIC_KEY_INIT_TRUE;
if (static_key_false(&key))
do unlikely code
else
do likely code
Or:
if (static_key_true(&key))
do likely code
else
do unlikely code
The static key is modified via:
static_key_slow_inc(&key);
...
static_key_slow_dec(&key);
The 'slow' prefix makes it abundantly clear that this is an
expensive operation.
I've updated all in-kernel code to use this everywhere. Note
that I (intentionally) have not pushed through the rename
blindly through to the lowest levels: the actual jump-label
patching arch facility should be named like that, so we want to
decouple jump labels from the static-key facility a bit.
On non-jump-label enabled architectures static keys default to
likely()/unlikely() branches.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jason Baron <jbaron@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: a.p.zijlstra@chello.nl
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Traditionally the kernel has refused to setup EFI at all if there's been
a mismatch in 32/64-bit mode between EFI and the kernel.
On some platforms that boot natively through EFI (Chrome OS being one),
we still need to get at least some of the static data such as memory
configuration out of EFI. Runtime services aren't as critical, and
it's a significant amount of work to implement switching between the
operating modes to call between kernel and firmware for thise cases. So
I'm ignoring it for now.
v5:
* Fixed some printk strings based on feedback
* Renamed 32/64-bit specific types to not have _ prefix
* Fixed bug in printout of efi runtime disablement
v4:
* Some of the earlier cleanup was accidentally reverted by this patch, fixed.
* Reworded some messages to not have to line wrap printk strings
v3:
* Reorganized to a series of patches to make it easier to review, and
do some of the cleanups I had left out before.
v2:
* Added graceful error handling for 32-bit kernel that gets passed
EFI data above 4GB.
* Removed some warnings that were missed in first version.
Signed-off-by: Olof Johansson <olof@lixom.net>
Link: http://lkml.kernel.org/r/1329081869-20779-6-git-send-email-olof@lixom.net
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
It's not perfect, but way better than before. Mark efi_enabled as false in
case of error and at least stop dereferencing pointers that are known to
be invalid.
The only significant missing piece is the lack of undoing the
memblock_reserve of the memory that efi marks as in use. On the other
hand, it's not a large amount of memory, and leaving it unavailable for
system use should be the safer choice anyway.
Signed-off-by: Olof Johansson <olof@lixom.net>
Link: http://lkml.kernel.org/r/1329081869-20779-5-git-send-email-olof@lixom.net
Acked-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Chris Metcalf
Dave Airlie
H. Peter Anvin
Jussi Kivilinna
Daniel J Blueman
Ingo Molnar
Thomas Gleixner
Srikar Dronamraju
Salman Qazi
Suresh Siddha
Peter Zijlstra
Peter Zijlstra
Grant Likely
Konrad Rzeszutek Wilk
Kirill A. Shutemov
Kees Cook
Greg Kroah-Hartman
Linus Torvalds
Nadav Har'El
Nicolae Mogoreanu
Davidlohr Bueso
Gleb Natapov
Avi Kivity
Jan Kiszka
Kevin Wolf
Takuya Yoshikawa
Raghavendra K T
Zachary Amsden
Marcelo Tosatti
Jan Beulich
Srivatsa S. Bhat
Daniel Drake
Masami Hiramatsu
Philip Prindeville
H.J. Lu
Al Viro
Stephane Eranian
Igor Mammedov
Julian Stecklina
Christian Borntraeger
Boris Ostrovsky
Carsten Otte
Xiao Guangrong
Alex Shi
Paul Gortmaker
Rafael J. Wysocki
Jiri Kosina
Myron Stowe
Joerg Roedel
H. Peter Anvin
Jonathan Nieder
Matt Fleming
Mark Wielaard
Siddhesh Poyarekar
Bobby Powers
Yinghai Lu
Steven Rostedt
Olof Johansson