linux.git/arch/x86/kernel/cpu/mcheck, branch v4.12

x86/MCE: Export memory_error()

2017-05-21T19:39:58+00:00

Export the function which checks whether an MCE is a memory error to
other users so that we can reuse the logic. Drop the boot_cpu_data use,
while at it, as mce.cpuvendor already has the CPU vendor in there.

Integrate a piece from a patch from Vishal Verma
 to export it for modules (nfit).

The main reason we're exporting it is that the nfit handler
nfit_handle_mce() needs to detect a memory error properly before doing
its recovery actions.

Signed-off-by: Borislav Petkov 
Cc: Tony Luck 
Cc: Vishal Verma 
Cc: 
Link: http://lkml.kernel.org/r/20170519093915.15413-2-bp@alien8.de
Signed-off-by: Thomas Gleixner

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

2017-05-02T03:48:33+00:00

Pull RAS updates from Ingo Molnar:
 "The main changes in this cycle were:

   - add the 'Corrected Errors Collector' kernel feature which collect
     and monitor correctable errors statistics and will preemptively
     (soft-)offline physical pages that have a suspiciously high error
     count.

   - handle MCE errors during kexec() more gracefully

   - factor out and deprecate the /dev/mcelog driver

   - ... plus misc fixes and cleanpus"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Check MCi_STATUS[MISCV] for usable addr on Intel only
  ACPI/APEI: Use setup_deferrable_timer()
  x86/mce: Update notifier priority check
  x86/mce: Enable PPIN for Knights Landing/Mill
  x86/mce: Do not register notifiers with invalid prio
  x86/mce: Factor out and deprecate the /dev/mcelog driver
  RAS: Add a Corrected Errors Collector
  x86/mce: Rename mce_log to mce_log_buffer
  x86/mce: Rename mce_log()'s argument
  x86/mce: Init some CPU features early
  x86/mce: Handle broadcasted MCE gracefully with kexec

x86/mce: Check MCi_STATUS[MISCV] for usable addr on Intel only

2017-04-19T10:04:46+00:00

mce_usable_address() does a bunch of basic sanity checks to verify
whether the address reported with the error is usable for further
processing. However, we do check MCi_STATUS[MISCV] and that is not
needed on AMD as that bit says that there's additional information about
the logged error in the MCi_MISCj banks.

But we don't need that to know whether the address is usable - we only
need to know whether the physical address is valid - i.e., ADDRV.

On Intel the MISCV bit is needed to perform additional checks to determine
whether the reported address is a physical one, etc.

Signed-off-by: Borislav Petkov 
Cc: Yazen Ghannam 
Cc: Tony Luck 
Cc: linux-edac 
Link: http://lkml.kernel.org/r/20170418183924.6agjkebilwqj26or@pd.tnic
Signed-off-by: Thomas Gleixner

x86/mce: Make the MCE notifier a blocking one

2017-04-18T20:23:48+00:00

The NFIT MCE handler callback (for handling media errors on NVDIMMs)
takes a mutex to add the location of a memory error to a list. But since
the notifier call chain for machine checks (x86_mce_decoder_chain) is
atomic, we get a lockdep splat like:

  BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
  in_atomic(): 1, irqs_disabled(): 0, pid: 4, name: kworker/0:0
  [..]
  Call Trace:
   dump_stack
   ___might_sleep
   __might_sleep
   mutex_lock_nested
   ? __lock_acquire
   nfit_handle_mce
   notifier_call_chain
   atomic_notifier_call_chain
   ? atomic_notifier_call_chain
   mce_gen_pool_process

Convert the notifier to a blocking one which gets to run only in process
context.

Boris: remove the notifier call in atomic context in print_mce(). For
now, let's print the MCE on the atomic path so that we can make sure
they go out and get logged at least.

Fixes: 6839a6d96f4e ("nfit: do an ARS scrub on hitting a latent media error")
Reported-by: Ross Zwisler 
Signed-off-by: Vishal Verma 
Acked-by: Tony Luck 
Cc: Dan Williams 
Cc: linux-edac 
Cc: x86-ml 
Cc: 
Link: http://lkml.kernel.org/r/20170411224457.24777-1-vishal.l.verma@intel.com
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner

x86/mce: Update notifier priority check

2017-04-18T08:27:52+00:00

Update the check which enforces the registration of MCE decoder notifier
callbacks with valid priority only, to include mcelog's priority.

Reported-by: kernel test robot 
Signed-off-by: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Stephen Rothwell 
Cc: Thomas Gleixner 
Cc: Tony Luck 
Cc: linux-edac 
Cc: lkp@01.org
Link: http://lkml.kernel.org/r/20170418073820.i6kl5tggcntwlisa@pd.tnic
Signed-off-by: Ingo Molnar

x86/mce: Enable PPIN for Knights Landing/Mill

2017-04-14T08:46:12+00:00

Intel Xeon Phi processors (KNL and KNM) support PPIN as well, so add their
CPUIDs to the whitelist of supported processors.

Signed-off-by: Piotr Luc 
Signed-off-by: Borislav Petkov 
Cc: Tony Luck 
Cc: linux-edac 
Link: http://lkml.kernel.org/r/20170408172004.8463-1-piotr.luc@intel.com
Link: http://lkml.kernel.org/r/20170413201056.10525-1-bp@alien8.de
Signed-off-by: Thomas Gleixner

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

2017-04-03T15:36:24+00:00

Pull RAS fix from Thomas Gleixner:
 "Prevent dmesg from being spammed when MCE logging is active"

* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Don't print MCEs when mcelog is active

x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs

2017-03-31T08:09:44+00:00

MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name.
However, MCA bank 3 is defined on Fam17h systems and can be accessed
using legacy MSRs. Without a name we get a stack trace on Fam17h systems
when trying to register sysfs files for bank 3 on kernels that don't
recognize Scalable MCA.

Call MCA bank 3 "decode_unit" since this is what it represents on
Fam17h. This will allow kernels without SMCA support to see this bank on
Fam17h+ and prevent the stack trace. This will not affect older systems
since this bank is reserved on them, i.e. it'll be ignored.

Tested on AMD Fam15h and Fam17h systems.

  WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal
  kobject: (ffff88085bb256c0): attempted to be registered with empty name!
  ...
  Call Trace:
   kobject_add_internal
   kobject_add
   kobject_create_and_add
   threshold_create_device
   threshold_init_device

Signed-off-by: Yazen Ghannam 
Signed-off-by: Borislav Petkov 
Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com
Signed-off-by: Thomas Gleixner

x86/mce: Do not register notifiers with invalid prio

2017-03-28T06:55:15+00:00

This is just a defensive precaution: do not register notifiers with a
priority which would disrupt the error handling in the notifiers with
prio higher than MCE_PRIO_EDAC.

Signed-off-by: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-edac 
Link: http://lkml.kernel.org/r/20170327093304.10683-7-bp@alien8.de
Signed-off-by: Ingo Molnar

x86/mce: Factor out and deprecate the /dev/mcelog driver

2017-03-28T06:55:01+00:00

Move all code relating to /dev/mcelog to a separate source file.
/dev/mcelog driver can now operate from the machine check notifier with
lowest prio.

Signed-off-by: Tony Luck 
[ Move the mce_helper and trigger functionality behind CONFIG_X86_MCELOG_LEGACY. ]
Signed-off-by: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-edac 
Link: http://lkml.kernel.org/r/20170327093304.10683-6-bp@alien8.de
[ Renamed CONFIG_X86_MCELOG to CONFIG_X86_MCELOG_LEGACY. ]
Signed-off-by: Ingo Molnar 

Signed-off-by: Ingo Molnar