diff options
| author | David Kaplan <david.kaplan@amd.com> | 2025-07-07 13:33:02 -0500 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2025-07-11 17:56:40 +0200 |
| commit | de6f0921ba49f5e07f57eb227dcb69ebb4776911 (patch) | |
| tree | a506f611e740c8497bc539245de62ec6f29c641f | |
| parent | 736565d4edcd8b6dad50fca0c0134e7918e3d61c (diff) | |
x86/bugs: Add attack vector controls for MMIO
Use attack vectors controls to determine if MMIO mitigation is required.
Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250707183316.1349127-8-david.kaplan@amd.com
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 438c482d4bb0..39ff556f35c1 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -639,8 +639,12 @@ static void __init mmio_select_mitigation(void) } /* Microcode will be checked in mmio_update_mitigation(). */ - if (mmio_mitigation == MMIO_MITIGATION_AUTO) - mmio_mitigation = MMIO_MITIGATION_VERW; + if (mmio_mitigation == MMIO_MITIGATION_AUTO) { + if (should_mitigate_vuln(X86_BUG_MMIO_STALE_DATA)) + mmio_mitigation = MMIO_MITIGATION_VERW; + else + mmio_mitigation = MMIO_MITIGATION_OFF; + } if (mmio_mitigation == MMIO_MITIGATION_OFF) return; @@ -655,7 +659,7 @@ static void __init mmio_select_mitigation(void) static void __init mmio_update_mitigation(void) { - if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA) || cpu_mitigations_off()) + if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) return; if (verw_clear_cpu_buf_mitigation_selected) @@ -703,7 +707,7 @@ static void __init mmio_apply_mitigation(void) if (!(x86_arch_cap_msr & ARCH_CAP_FBSDP_NO)) static_branch_enable(&cpu_buf_idle_clear); - if (mmio_nosmt || cpu_mitigations_auto_nosmt()) + if (mmio_nosmt || smt_mitigations == SMT_MITIGATIONS_ON) cpu_smt_disable(false); } |