perf/x86/amd/ibs: Work around erratum #1197
authorKim Phillips <kim.phillips@amd.com>
Tue, 17 Aug 2021 22:10:42 +0000 (17:10 -0500)
committerIngo Molnar <mingo@kernel.org>
Thu, 26 Aug 2021 06:58:02 +0000 (08:58 +0200)
commit26db2e0c51fe83e1dd852c1321407835b481806e
tree30b289fd7faadcd661cbad57e2c0740023e77ad5
parent0b3a8738b76fe2087f7bc2bd59f4c78504c79180
perf/x86/amd/ibs: Work around erratum #1197

Erratum #1197 "IBS (Instruction Based Sampling) Register State May be
Incorrect After Restore From CC6" is published in a document:

  "Revision Guide for AMD Family 19h Models 00h-0Fh Processors" 56683 Rev. 1.04 July 2021

  https://bugzilla.kernel.org/show_bug.cgi?id=206537

Implement the erratum's suggested workaround and ignore IBS samples if
MSRC001_1031 == 0.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210817221048.88063-3-kim.phillips@amd.com
arch/x86/events/amd/ibs.c