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Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 67561e5c2154..bf5de097e1a9 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1744,6 +1744,17 @@ static void __init its_apply_mitigation(void) } } =20 +#ifdef CONFIG_DYNAMIC_MITIGATIONS +static void its_reset_mitigation(void) +{ + setup_clear_cpu_cap(X86_FEATURE_INDIRECT_THUNK_ITS); + setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + x86_return_thunk =3D __x86_return_thunk; + its_mitigation =3D IS_ENABLED(CONFIG_MITIGATION_ITS) ? + ITS_MITIGATION_AUTO : ITS_MITIGATION_OFF; +} +#endif + #undef pr_fmt #define pr_fmt(fmt) "Transient Scheduler Attacks: " fmt =20 @@ -3966,5 +3977,6 @@ void arch_cpu_reset_mitigations(void) srso_reset_mitigation(); gds_reset_mitigation(); bhi_reset_mitigation(); + its_reset_mitigation(); } #endif --=20 2.34.1