diff options
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 28 |
1 files changed, 9 insertions, 19 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index dd8379d84445..03ef962a6992 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -766,6 +766,15 @@ static void early_init_amd(struct cpuinfo_x86 *c) if (cpu_has(c, X86_FEATURE_TOPOEXT)) smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1; + + if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) { + if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB)) + setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE); + else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) { + setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE); + setup_force_cpu_cap(X86_FEATURE_SBPB); + } + } } static void init_amd_k8(struct cpuinfo_x86 *c) @@ -1301,25 +1310,6 @@ void amd_check_microcode(void) on_each_cpu(zenbleed_check_cpu, NULL, 1); } -bool cpu_has_ibpb_brtype_microcode(void) -{ - switch (boot_cpu_data.x86) { - /* Zen1/2 IBPB flushes branch type predictions too. */ - case 0x17: - return boot_cpu_has(X86_FEATURE_AMD_IBPB); - case 0x19: - /* Poke the MSR bit on Zen3/4 to check its presence. */ - if (!wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) { - setup_force_cpu_cap(X86_FEATURE_SBPB); - return true; - } else { - return false; - } - default: - return false; - } -} - /* * Issue a DIV 0/1 insn to clear any division data from previous DIV * operations. |