diff options
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index f41d871f0622..b9d0509e5e5e 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1657,28 +1657,43 @@ early_param("tsa", tsa_parse_cmdline); static void __init tsa_select_mitigation(void) { - if (cpu_mitigations_off() || !boot_cpu_has_bug(X86_BUG_TSA)) { + if (!boot_cpu_has_bug(X86_BUG_TSA)) { tsa_mitigation = TSA_MITIGATION_NONE; return; } + if (tsa_mitigation == TSA_MITIGATION_AUTO) { + bool vm = false, uk = false; + + tsa_mitigation = TSA_MITIGATION_NONE; + + if (cpu_attack_vector_mitigated(CPU_MITIGATE_USER_KERNEL) || + cpu_attack_vector_mitigated(CPU_MITIGATE_USER_USER)) { + tsa_mitigation = TSA_MITIGATION_USER_KERNEL; + uk = true; + } + + if (cpu_attack_vector_mitigated(CPU_MITIGATE_GUEST_HOST) || + cpu_attack_vector_mitigated(CPU_MITIGATE_GUEST_GUEST)) { + tsa_mitigation = TSA_MITIGATION_VM; + vm = true; + } + + if (uk && vm) + tsa_mitigation = TSA_MITIGATION_FULL; + } + if (tsa_mitigation == TSA_MITIGATION_NONE) return; - if (!boot_cpu_has(X86_FEATURE_VERW_CLEAR)) { + if (!boot_cpu_has(X86_FEATURE_VERW_CLEAR)) tsa_mitigation = TSA_MITIGATION_UCODE_NEEDED; - goto out; - } - - if (tsa_mitigation == TSA_MITIGATION_AUTO) - tsa_mitigation = TSA_MITIGATION_FULL; /* * No need to set verw_clear_cpu_buf_mitigation_selected - it * doesn't fit all cases here and it is not needed because this * is the only VERW-based mitigation on AMD. */ -out: pr_info("%s\n", tsa_strings[tsa_mitigation]); } |