diff options
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index dd32dbc7c33e..571abf808ea3 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -880,6 +880,15 @@ 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) @@ -920,6 +929,10 @@ static void init_amd(struct cpuinfo_x86 *c) if (c->x86 >= 0x10) set_cpu_cap(c, X86_FEATURE_REP_GOOD); + /* AMD FSRM also implies FSRS */ + if (cpu_has(c, X86_FEATURE_FSRM)) + set_cpu_cap(c, X86_FEATURE_FSRS); + /* get apicid instead of initial apic id from cpuid */ c->apicid = hard_smp_processor_id(); |