diff options
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 1f8c1c51d057..fa32615db71d 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -3400,6 +3400,28 @@ void cpu_bugs_smt_update(void) break; } + switch (vmscape_mitigation) { + case VMSCAPE_MITIGATION_NONE: + case VMSCAPE_MITIGATION_AUTO: + break; + case VMSCAPE_MITIGATION_IBPB_ON_VMEXIT: + case VMSCAPE_MITIGATION_IBPB_EXIT_TO_USER: + /* + * Hypervisors can be attacked across-threads, warn for SMT when + * STIBP is not already enabled system-wide. + * + * Intel eIBRS (!AUTOIBRS) implies STIBP on. + */ + if (!sched_smt_active() || + spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT || + spectre_v2_user_stibp == SPECTRE_V2_USER_STRICT_PREFERRED || + (spectre_v2_in_eibrs_mode(spectre_v2_enabled) && + !boot_cpu_has(X86_FEATURE_AUTOIBRS))) + break; + pr_warn_once(VMSCAPE_MSG_SMT); + break; + } + mutex_unlock(&spec_ctrl_mutex); } |