linux.git/arch/x86/kernel/cpu, branch v3.15

Revert "x86/smpboot: Initialize secondary CPU only if master CPU will wait for it"

2014-06-08T17:09:49+00:00

This reverts commit 3e1a878b7ccdb31da6d9d2b855c72ad87afeba3f.

It came in very late, and already has one reported failure: Sitsofe
reports that the current tree fails to boot on his EeePC, and bisected
it down to this.  Rather than waste time trying to figure out what's
wrong, just revert it.

Reported-by: Sitsofe Wheeler 
Cc: Igor Mammedov 
Cc: Toshi Kani 
Cc: Thomas Gleixner 
Acked-by: Ingo Molnar 
Signed-off-by: Linus Torvalds

x86/smpboot: Initialize secondary CPU only if master CPU will wait for it

2014-06-05T14:33:08+00:00

Hang is observed on virtual machines during CPU hotplug,
especially in big guests with many CPUs. (It reproducible
more often if host is over-committed).

It happens because master CPU gives up waiting on
secondary CPU and allows it to run wild. As result
AP causes locking or crashing system. For example
as described here:

   https://lkml.org/lkml/2014/3/6/257

If master CPU have sent STARTUP IPI successfully,
and AP signalled to master CPU that it's ready
to start initialization, make master CPU wait
indefinitely till AP is onlined.
To ensure that AP won't ever run wild, make it
wait at early startup till master CPU confirms its
intention to wait for AP. If AP doesn't respond in 10
seconds, the master CPU will timeout and cancel
AP onlining.

Signed-off-by: Igor Mammedov 
Acked-by: Toshi Kani 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/1401975765-22328-4-git-send-email-imammedo@redhat.com
Signed-off-by: Ingo Molnar

Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-05-23T17:02:34+00:00

Pull perf fixes from Ingo Molnar:
 "The biggest changes are fixes for races that kept triggering Trinity
  crashes, plus liblockdep build fixes and smaller misc fixes.

  The liblockdep bits in perf/urgent are a pull mistake - they should
  have been in locking/urgent - but by the time I noticed other commits
  were added and testing was done :-/ Sorry about that"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()
  perf: Prevent false warning in perf_swevent_add
  perf: Limit perf_event_attr::sample_period to 63 bits
  tools/liblockdep: Remove all build files when doing make clean
  tools/liblockdep: Build liblockdep from tools/Makefile
  perf/x86/intel: Fix Silvermont's event constraints
  perf: Fix perf_event_init_context()
  perf: Fix race in removing an event

x86, rdrand: When nordrand is specified, disable RDSEED as well

2014-05-12T03:25:20+00:00

One can logically expect that when the user has specified "nordrand",
the user doesn't want any use of the CPU random number generator,
neither RDRAND nor RDSEED, so disable both.

Reported-by: Stephan Mueller 
Cc: Theodore Ts'o 
Link: http://lkml.kernel.org/r/21542339.0lFnPSyGRS@myon.chronox.de
Signed-off-by: H. Peter Anvin

perf/x86/intel: Fix Silvermont's event constraints

2014-05-07T09:33:16+00:00

Event 0x013c is not the same as fixed counter2, remove it from
Silvermont's event constraints.

Signed-off-by: Yan, Zheng 
Signed-off-by: Peter Zijlstra 
Cc: Arnaldo Carvalho de Melo 
Cc: Stephane Eranian 
Link: http://lkml.kernel.org/r/1398755081-12471-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar

asmlinkage, x86: Add explicit __visible to arch/x86/*

2014-05-05T23:07:44+00:00

As requested by Linus add explicit __visible to the asmlinkage users.
This marks all functions visible to assembler.

Tree sweep for arch/x86/*

Signed-off-by: Andi Kleen 
Link: http://lkml.kernel.org/r/1398984278-29319-3-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin

perf/x86: Fix RAPL rdmsrl_safe() usage

2014-04-24T06:12:41+00:00

This patch fixes a bug introduced by:

  24223657806a ("perf/x86/intel: Use rdmsrl_safe() when initializing RAPL PMU")

The rdmsrl_safe() function returns 0 on success.
The current code was failing to detect the RAPL PMU
on real hardware  (missing /sys/devices/power) because
the return value of rdmsrl_safe() was misinterpreted.

Signed-off-by: Stephane Eranian 
Acked-by: Borislav Petkov 
Acked-by: Venkatesh Srinivas 
Cc: peterz@infradead.org
Cc: zheng.z.yan@intel.com
Link: http://lkml.kernel.org/r/20140423170418.GA12767@quad
Signed-off-by: Ingo Molnar

Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-04-19T17:41:43+00:00

Pull x86 fix from Ingo Molnar:
 "This fixes the preemption-count imbalance crash reported by Owen
  Kibel"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Fix CMCI preemption bugs

perf/x86/intel: Use rdmsrl_safe() when initializing RAPL PMU

2014-04-18T10:14:26+00:00

CPUs which should support the RAPL counters according to
Family/Model/Stepping may still issue #GP when attempting to access
the RAPL MSRs. This may happen when Linux is running under KVM and
we are passing-through host F/M/S data, for example. Use rdmsrl_safe
to first access the RAPL_POWER_UNIT MSR; if this fails, do not
attempt to use this PMU.

Signed-off-by: Venkatesh Srinivas 
Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1394739386-22260-1-git-send-email-venkateshs@google.com
Cc: zheng.z.yan@intel.com
Cc: eranian@google.com
Cc: ak@linux.intel.com
Cc: linux-kernel@vger.kernel.org
[ The patch also silently fixes another bug: rapl_pmu_init() didn't handle the memory alloc failure case previously. ]
Signed-off-by: Ingo Molnar

x86/mce: Fix CMCI preemption bugs

2014-04-17T08:28:42+00:00

The following commit:

  27f6c573e0f7 ("x86, CMCI: Add proper detection of end of CMCI storms")

Added two preemption bugs:

 - machine_check_poll() does a get_cpu_var() without a matching
   put_cpu_var(), which causes preemption imbalance and crashes upon
   bootup.

 - it does percpu ops without disabling preemption. Preemption is not
   disabled due to the mistaken use of a raw spinlock.

To fix these bugs fix the imbalance and change
cmci_discover_lock to a regular spinlock.

Reported-by: Owen Kibel 
Reported-by: Linus Torvalds 
Signed-off-by: Ingo Molnar 
Cc: Chen, Gong 
Cc: Josh Boyer 
Cc: Tony Luck 
Cc: Peter Zijlstra 
Cc: Alexander Todorov 
Cc: Borislav Petkov 
Link: http://lkml.kernel.org/n/tip-jtjptvgigpfkpvtQxpEk1at2@git.kernel.org
Signed-off-by: Ingo Molnar 
--
 arch/x86/kernel/cpu/mcheck/mce.c       |    4 +---
 arch/x86/kernel/cpu/mcheck/mce_intel.c |   18 +++++++++---------
 2 files changed, 10 insertions(+), 12 deletions(-)