6.6-stable review patch. If anyone has any objections, please let me know.
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From: Borislav Petkov (AMD) bp@alien8.de
[ Upstream commit a7c32a1ae9ee43abfe884f5af376877c4301d166 ]
Call it on the affected CPU generations.
No functional changes.
Signed-off-by: Borislav Petkov (AMD) bp@alien8.de Reviewed-by: Nikolay Borisov nik.borisov@suse.com Link: http://lore.kernel.org/r/20231120104152.13740-3-bp@alien8.de Stable-dep-of: c7b2edd8377b ("perf/x86/amd/core: Update and fix stalled-cycles-* events for Zen 2 and later") Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kernel/cpu/amd.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 5391385707b3f..28c3a1045b060 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -988,6 +988,19 @@ static void init_amd_bd(struct cpuinfo_x86 *c) clear_rdrand_cpuid_bit(c); }
+static void fix_erratum_1386(struct cpuinfo_x86 *c) +{ + /* + * Work around Erratum 1386. The XSAVES instruction malfunctions in + * certain circumstances on Zen1/2 uarch, and not all parts have had + * updated microcode at the time of writing (March 2023). + * + * Affected parts all have no supervisor XSAVE states, meaning that + * the XSAVEC instruction (which works fine) is equivalent. + */ + clear_cpu_cap(c, X86_FEATURE_XSAVES); +} + void init_spectral_chicken(struct cpuinfo_x86 *c) { #ifdef CONFIG_CPU_UNRET_ENTRY @@ -1008,15 +1021,6 @@ void init_spectral_chicken(struct cpuinfo_x86 *c) } } #endif - /* - * Work around Erratum 1386. The XSAVES instruction malfunctions in - * certain circumstances on Zen1/2 uarch, and not all parts have had - * updated microcode at the time of writing (March 2023). - * - * Affected parts all have no supervisor XSAVE states, meaning that - * the XSAVEC instruction (which works fine) is equivalent. - */ - clear_cpu_cap(c, X86_FEATURE_XSAVES); }
static void init_amd_zn(struct cpuinfo_x86 *c) @@ -1085,10 +1089,12 @@ static void zenbleed_check(struct cpuinfo_x86 *c)
static void init_amd_zen(struct cpuinfo_x86 *c) { + fix_erratum_1386(c); }
static void init_amd_zen2(struct cpuinfo_x86 *c) { + fix_erratum_1386(c); }
static void init_amd_zen3(struct cpuinfo_x86 *c)