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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 9139c8187913..9a9d5309aa56 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -993,6 +993,17 @@ static void __init srbds_apply_mitigation(void) update_srbds_msr(); } =20 +#ifdef CONFIG_DYNAMIC_MITIGATIONS +static void srbds_reset_mitigation(void) +{ + /* To cause the MSR bit to be cleared */ + srbds_mitigation =3D SRBDS_MITIGATION_FULL; + update_srbds_msr(); + srbds_mitigation =3D IS_ENABLED(CONFIG_MITIGATION_SRBDS) ? + SRBDS_MITIGATION_AUTO : SRBDS_MITIGATION_OFF; +} +#endif + static int __init srbds_parse_cmdline(char *str) { if (!str) @@ -3913,5 +3924,6 @@ void arch_cpu_reset_mitigations(void) l1tf_reset_mitigation(); mds_reset_mitigation(); mmio_reset_mitigation(); + srbds_reset_mitigation(); } #endif --=20 2.34.1