On 18/01/21 09:47, Jay Zhou wrote:
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 <[email protected]> Signed-off-by: Shengen Zhuang <[email protected]> --- arch/x86/kvm/x86.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9a8969a..9025c76 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -105,6 +105,7 @@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); static void store_regs(struct kvm_vcpu *vcpu); @@ -4230,6 +4231,9 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu, { process_nmi(vcpu);+ if (kvm_check_request(KVM_REQ_SMI, vcpu))+ process_smi(vcpu); + /* * In guest mode, payload delivery should be deferred, * so that the L1 hypervisor can intercept #PF before
Queued, thanks. Paolo
