if (boot_cpu_has_bug(X86_BUG_MDS) || (boot_cpu_has_bug(X86_BUG_TAA) &&
boot_cpu_has(X86_FEATURE_RTM)))
setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF);
+
+ /*
+ * X86_FEATURE_CLEAR_CPU_BUF could be enabled by other VERW based
+ * mitigations, disable KVM-only mitigation in that case.
+ */
+ if (boot_cpu_has(X86_FEATURE_CLEAR_CPU_BUF))
+ static_branch_disable(&mmio_stale_data_clear);
else
static_branch_enable(&mmio_stale_data_clear);
taa_mitigation = TAA_MITIGATION_VERW;
taa_select_mitigation();
}
- if (mmio_mitigation == MMIO_MITIGATION_OFF &&
- boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) {
+ /*
+ * MMIO_MITIGATION_OFF is not checked here so that mmio_stale_data_clear
+ * gets updated correctly as per X86_FEATURE_CLEAR_CPU_BUF state.
+ */
+ if (boot_cpu_has_bug(X86_BUG_MMIO_STALE_DATA)) {
mmio_mitigation = MMIO_MITIGATION_VERW;
mmio_select_mitigation();
}