x86/cpufeature: Create a new synthetic cpu capability for machine check recovery

The Intel Software Developer Manual describes bit 24 in the MCG_CAP
MSR:

   MCG_SER_P (software error recovery support present) flag,
   bit 24 — Indicates (when set) that the processor supports
   software error recovery

But only some models with this capability bit set will actually
generate recoverable machine checks.

Check the model name and set a synthetic capability bit. Provide
a command line option to set this bit anyway in case the kernel
doesn't recognise the model name.

Signed-off-by: Tony Luck <[email protected]>
Reviewed-by: Borislav Petkov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/2e5bfb23c89800a036fb8a45fa97a74bb16bc362.1455732970.git.tony.luck@intel.com
Signed-off-by: Ingo Molnar <[email protected]>
This commit is contained in:
Tony Luck 2016-02-17 10:20:13 -08:00 • committed by Ingo Molnar
commit 0f68c088c0
4 changed files with 17 additions and 0 deletions

View file

@ -60,6 +60,8 @@ Machine check
threshold to 1. Enabling this may make memory predictive failure
analysis less effective if the bios sets thresholds for memory
errors since we will not see details for all errors.
mce=recovery
Force-enable recoverable machine check code paths
nomce (for compatibility with i386): same as mce=off