tree 6671d6f3e544572a3fc0e902685130aa76430fd6
parent 1d061bbd511ba479817034300e42f6e46f6fa33b
author Kim Phillips <kim.phillips@amd.com> 1629238242 -0500
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1632303775 +0200

perf/x86/amd/ibs: Work around erratum #1197

[ Upstream commit 26db2e0c51fe83e1dd852c1321407835b481806e ]

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
Signed-off-by: Sasha Levin <sashal@kernel.org>