From: Jay Zhou Date: Mon, 18 Jan 2021 08:47:20 +0000 (+0800) Subject: KVM: x86: get smi pending status correctly X-Git-Tag: v4.9.255~16 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f5d6818a56724636c8a2d9ff070decf32d2de4dd;p=thirdparty%2Fkernel%2Fstable.git KVM: x86: get smi pending status correctly commit 1f7becf1b7e21794fc9d460765fe09679bc9b9e0 upstream. The injection process of smi has two steps: Qemu KVM Step1: cpu->interrupt_request &= \ ~CPU_INTERRUPT_SMI; kvm_vcpu_ioctl(cpu, KVM_SMI) call kvm_vcpu_ioctl_smi() and kvm_make_request(KVM_REQ_SMI, vcpu); Step2: kvm_vcpu_ioctl(cpu, KVM_RUN, 0) call process_smi() if kvm_check_request(KVM_REQ_SMI, vcpu) is true, mark vcpu->arch.smi_pending = true; The vcpu->arch.smi_pending will be set true in step2, unfortunately if vcpu paused between step1 and step2, the kvm_run->immediate_exit will be set and vcpu has to exit to Qemu immediately during step2 before mark vcpu->arch.smi_pending true. During VM migration, Qemu will get the smi pending status from KVM using KVM_GET_VCPU_EVENTS ioctl at the downtime, then the smi pending status will be lost. Signed-off-by: Jay Zhou Signed-off-by: Shengen Zhuang Message-Id: <20210118084720.1585-1-jianjay.zhou@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 3c0f9be107e42..98fb3a7240371 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -97,6 +97,7 @@ static u64 __read_mostly efer_reserved_bits = ~((u64)EFER_SCE); static void update_cr8_intercept(struct kvm_vcpu *vcpu); static void process_nmi(struct kvm_vcpu *vcpu); +static void process_smi(struct kvm_vcpu *vcpu); static void enter_smm(struct kvm_vcpu *vcpu); static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags); @@ -3199,6 +3200,10 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, struct kvm_vcpu_events *events) { process_nmi(vcpu); + + if (kvm_check_request(KVM_REQ_SMI, vcpu)) + process_smi(vcpu); + events->exception.injected = vcpu->arch.exception.pending && !kvm_exception_is_soft(vcpu->arch.exception.nr);