Commit Graph

6 Commits

Author SHA1 Message Date
Tony Luck
aaefca8e30 x86/mce: Don't check for the overflow bit on action optional machine checks
We currently do not process SRAO (Software Recoverable Action Optional)
machine checks if they are logged with the overflow bit set to 1 in the
machine check bank status register. This is overly conservative.

There are two cases where we could end up with an SRAO+OVER log based
on the SDM volume 3 overwrite rules in "Table 15-8. Overwrite Rules for
UC, CE, and UCR Errors"

1) First a corrected error is logged, then the SRAO error overwrites.
   The second error overwrites the first because uncorrected errors
   have a higher severity than corrected errors.
2) The SRAO error was logged first, followed by a correcetd error.
   In this case the first error is retained in the bank.

So in either case the machine check bank will contain the address
of the SRAO error. So we can process that even if the overflow bit
was set.

Reported-by: Yongkai Wu <yongkaiwu@tencent.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190718182920.32621-1-tony.luck@intel.com
2019-08-05 09:34:02 +02:00
Linus Torvalds
090bc5a2a9 Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RAS updates from Ingo Molnar:
 "Boris is on vacation so I'm sending the RAS bits this time. The main
  changes were:

   - Various RAS/CEC improvements and fixes by Borislav Petkov:
       - error insertion fixes
       - offlining latency fix
       - memory leak fix
       - additional sanity checks
       - cleanups
       - debug output improvements

   - More SMCA enhancements by Yazen Ghannam:
       - make banks truly per-CPU which they are in the hardware
       - don't over-cache certain registers
       - make the number of MCA banks per-CPU variable

     The long term goal with these changes is to support future
     heterogenous SMCA extensions.

   - Misc fixes and improvements"

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce: Do not check return value of debugfs_create functions
  x86/MCE: Determine MCA banks' init state properly
  x86/MCE: Make the number of MCA banks a per-CPU variable
  x86/MCE/AMD: Don't cache block addresses on SMCA systems
  x86/MCE: Make mce_banks a per-CPU array
  x86/MCE: Make struct mce_banks[] static
  RAS/CEC: Add copyright
  RAS/CEC: Add CONFIG_RAS_CEC_DEBUG and move CEC debug features there
  RAS/CEC: Dump the different array element sections
  RAS/CEC: Rename count_threshold to action_threshold
  RAS/CEC: Sanity-check array on every insertion
  RAS/CEC: Fix potential memory leak
  RAS/CEC: Do not set decay value on error
  RAS/CEC: Check count_threshold unconditionally
  RAS/CEC: Fix pfn insertion
2019-07-08 16:31:06 -07:00
Greg Kroah-Hartman
6e4f929ea8 x86/mce: Do not check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

The only way this can fail is if:

 * debugfs superblock can not be pinned - something really went wrong with the
 vfs layer.
 * file is created with same name - the caller's fault.
 * new_inode() fails - happens if memory is exhausted.

so failing to clean up debugfs properly is the least of the system's
sproblems in uch a situation.

 [ bp: Extend commit message, remove unused err var in inject_init(). ]

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190612151531.GA16278@kroah.com
2019-06-14 16:04:21 +02:00
Thomas Gleixner
b886d83c5b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:17 +02:00
Tony Luck
41f035a86b x86/mce: Improve error message when kernel cannot recover, p2
In

  c7d606f560 ("x86/mce: Improve error message when kernel cannot recover")

a case was added for a machine check caused by a DATA access to poison
memory from the kernel. A case should have been added also for an
uncorrectable error during an instruction fetch in the kernel.

Add that extra case so the error message now reads:

  mce: [Hardware Error]: Machine check: Instruction fetch error in kernel

Fixes: c7d606f560 ("x86/mce: Improve error message when kernel cannot recover")
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190225205940.15226-1-tony.luck@intel.com
2019-02-25 23:21:35 +01:00
Borislav Petkov
21afaf1813 x86/mce: Streamline MCE subsystem's naming
Rename the containing folder to "mce" which is the most widespread name.
Drop the "mce[-_]" filename prefix of some compilation units (while
others don't have it).

This unifies the file naming in the MCE subsystem:

mce/
|-- amd.c
|-- apei.c
|-- core.c
|-- dev-mcelog.c
|-- genpool.c
|-- inject.c
|-- intel.c
|-- internal.h
|-- Makefile
|-- p5.c
|-- severity.c
|-- therm_throt.c
|-- threshold.c
`-- winchip.c

No functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20181205141323.14995-1-bp@alien8.de
2018-12-05 18:00:29 +01:00