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Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 5668a8b8821b..9139c8187913 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -787,6 +787,16 @@ static void __init mmio_apply_mitigation(void) cpu_smt_disable(false); } =20 +#ifdef CONFIG_DYNAMIC_MITIGATIONS +static void mmio_reset_mitigation(void) +{ + static_branch_disable(&cpu_buf_vm_clear); + static_branch_disable(&cpu_buf_idle_clear); + mmio_mitigation =3D IS_ENABLED(CONFIG_MITIGATION_MMIO_STALE_DATA) ? + MMIO_MITIGATION_AUTO : MMIO_MITIGATION_OFF; +} +#endif + static int __init mmio_stale_data_parse_cmdline(char *str) { if (!boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) @@ -3902,5 +3912,6 @@ void arch_cpu_reset_mitigations(void) ssb_reset_mitigation(); l1tf_reset_mitigation(); mds_reset_mitigation(); + mmio_reset_mitigation(); } #endif --=20 2.34.1