On Fri, Oct 27, 2023 at 07:39:12AM -0700, Pawan Gupta wrote: > - vmx_disable_fb_clear(vmx); > + /* > + * Optimize the latency of VERW in guests for MMIO mitigation. Skip > + * the optimization when MDS mitigation(later in asm) is enabled. > + */ > + if (!cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF)) > + vmx_disable_fb_clear(vmx); > > if (vcpu->arch.cr2 != native_read_cr2()) > native_write_cr2(vcpu->arch.cr2); > @@ -7248,7 +7256,8 @@ static noinstr void vmx_vcpu_enter_exit(struct kvm_vcpu *vcpu, > > vmx->idt_vectoring_info = 0; > > - vmx_enable_fb_clear(vmx); > + if (!cpu_feature_enabled(X86_FEATURE_CLEAR_CPU_BUF)) > + vmx_enable_fb_clear(vmx); > It may be cleaner to instead check X86_FEATURE_CLEAR_CPU_BUF when setting vmx->disable_fb_clear in the first place, in vmx_update_fb_clear_dis(). -- Josh
