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Disable SMT if cross-thread protection is desired. 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 2168e75bc1ac..ecfd7d728ac5 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -2884,17 +2884,23 @@ static void override_cache_bits(struct cpuinfo_x86 = *c) =20 static void __init l1tf_select_mitigation(void) { - if (!boot_cpu_has_bug(X86_BUG_L1TF) || cpu_mitigations_off()) { + if (!boot_cpu_has_bug(X86_BUG_L1TF)) { l1tf_mitigation =3D L1TF_MITIGATION_OFF; return; } =20 - if (l1tf_mitigation =3D=3D L1TF_MITIGATION_AUTO) { - if (cpu_mitigations_auto_nosmt()) - l1tf_mitigation =3D L1TF_MITIGATION_FLUSH_NOSMT; - else - l1tf_mitigation =3D L1TF_MITIGATION_FLUSH; + if (l1tf_mitigation !=3D L1TF_MITIGATION_AUTO) + return; + + if (!should_mitigate_vuln(X86_BUG_L1TF)) { + l1tf_mitigation =3D L1TF_MITIGATION_OFF; + return; } + + if (smt_mitigations =3D=3D SMT_MITIGATIONS_ON) + l1tf_mitigation =3D L1TF_MITIGATION_FLUSH_NOSMT; + else + l1tf_mitigation =3D L1TF_MITIGATION_FLUSH; } =20 static void __init l1tf_apply_mitigation(void) --=20 2.34.1