]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
x86/cpu/amd: Fix workaround for erratum 1054
authorSandipan Das <sandipan.das@amd.com>
Fri, 18 Apr 2025 06:19:40 +0000 (11:49 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 25 Apr 2025 08:45:50 +0000 (10:45 +0200)
commit5e036349bb0106e22d5bffb0de4727b0c9aa1a5e
tree7025c5765e325c7787b1684c80336946f34933c2
parent971ba6a64c53fbe3378d11d7295a9fc81c3695ee
x86/cpu/amd: Fix workaround for erratum 1054

commit 263e55949d8902a6a09bdb92a1ab6a3f67231abe upstream.

Erratum 1054 affects AMD Zen processors that are a part of Family 17h
Models 00-2Fh and the workaround is to not set HWCR[IRPerfEn]. However,
when X86_FEATURE_ZEN1 was introduced, the condition to detect unaffected
processors was incorrectly changed in a way that the IRPerfEn bit gets
set only for unaffected Zen 1 processors.

Ensure that HWCR[IRPerfEn] is set for all unaffected processors. This
includes a subset of Zen 1 (Family 17h Models 30h and above) and all
later processors. Also clear X86_FEATURE_IRPERF on affected processors
so that the IRPerfCount register is not used by other entities like the
MSR PMU driver.

Fixes: 232afb557835 ("x86/CPU/AMD: Add X86_FEATURE_ZEN1")
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/caa057a9d6f8ad579e2f1abaa71efbd5bd4eaf6d.1744956467.git.sandipan.das@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/cpu/amd.c