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Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 56d3bf343d1f..ba7c2a1ea98f 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -595,15 +595,21 @@ static const char * const mmio_strings[] =3D { static void __init mmio_select_mitigation(void) { if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA) || - boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN) || - cpu_mitigations_off()) { + boot_cpu_has_bug(X86_BUG_MMIO_UNKNOWN)) { mmio_mitigation =3D MMIO_MITIGATION_OFF; return; } =20 /* Microcode will be checked in mmio_update_mitigation(). */ - if (mmio_mitigation =3D=3D MMIO_MITIGATION_AUTO) - mmio_mitigation =3D MMIO_MITIGATION_VERW; + if (mmio_mitigation =3D=3D MMIO_MITIGATION_AUTO) { + if (should_mitigate_vuln(X86_BUG_MMIO_STALE_DATA)) + mmio_mitigation =3D MMIO_MITIGATION_VERW; + else + mmio_mitigation =3D MMIO_MITIGATION_OFF; + } + + if (mmio_mitigation =3D=3D MMIO_MITIGATION_OFF) + return; =20 /* * Enable CPU buffer clear mitigation for host and VMM, if also affected @@ -615,7 +621,7 @@ static void __init mmio_select_mitigation(void) =20 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; =20 if (verw_mitigation_selected) @@ -665,7 +671,7 @@ static void __init mmio_apply_mitigation(void) if (!(x86_arch_cap_msr & ARCH_CAP_FBSDP_NO)) static_branch_enable(&mds_idle_clear); =20 - if (mmio_nosmt || cpu_mitigations_auto_nosmt()) + if (mmio_nosmt || smt_mitigations =3D=3D SMT_MITIGATIONS_ON) cpu_smt_disable(false); } =20 --=20 2.34.1