diff options
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 27e177f7ef43..26ad7ca423e7 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -70,6 +70,11 @@ static const int amd_erratum_383[] = static const int amd_erratum_1054[] = AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0, 0, 0x2f, 0xf)); +static const int amd_zenbleed[] = + AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x17, 0x30, 0x0, 0x4f, 0xf), + AMD_MODEL_RANGE(0x17, 0x60, 0x0, 0x7f, 0xf), + AMD_MODEL_RANGE(0x17, 0xa0, 0x0, 0xaf, 0xf)); + static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum) { int osvw_id = *erratum++; @@ -978,6 +983,47 @@ static void init_amd_zn(struct cpuinfo_x86 *c) } } +static bool cpu_has_zenbleed_microcode(void) +{ + u32 good_rev = 0; + + switch (boot_cpu_data.x86_model) { + case 0x30 ... 0x3f: good_rev = 0x0830107a; break; + case 0x60 ... 0x67: good_rev = 0x0860010b; break; + case 0x68 ... 0x6f: good_rev = 0x08608105; break; + case 0x70 ... 0x7f: good_rev = 0x08701032; break; + case 0xa0 ... 0xaf: good_rev = 0x08a00008; break; + + default: + return false; + break; + } + + if (boot_cpu_data.microcode < good_rev) + return false; + + return true; +} + +static void zenbleed_check(struct cpuinfo_x86 *c) +{ + if (!cpu_has_amd_erratum(c, amd_zenbleed)) + return; + + if (cpu_has(c, X86_FEATURE_HYPERVISOR)) + return; + + if (!cpu_has(c, X86_FEATURE_AVX)) + return; + + if (!cpu_has_zenbleed_microcode()) { + pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n"); + msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT); + } else { + msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT); + } +} + static void init_amd(struct cpuinfo_x86 *c) { early_init_amd(c); @@ -1082,6 +1128,8 @@ static void init_amd(struct cpuinfo_x86 *c) if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) && cpu_has(c, X86_FEATURE_AUTOIBRS)) WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS)); + + zenbleed_check(c); } #ifdef CONFIG_X86_32 @@ -1230,3 +1278,15 @@ u32 amd_get_highest_perf(void) return 255; } EXPORT_SYMBOL_GPL(amd_get_highest_perf); + +static void zenbleed_check_cpu(void *unused) +{ + struct cpuinfo_x86 *c = &cpu_data(smp_processor_id()); + + zenbleed_check(c); +} + +void amd_check_microcode(void) +{ + on_each_cpu(zenbleed_check_cpu, NULL, 1); +} |