On Thu, 2022-08-11 at 17:06 -0400, Paolo Bonzini wrote:

From: Sean Christopherson seanjc@google.com

Set KVM_REQ_EVENT when MTF becomes pending to ensure that KVM will run through inject_pending_event() and thus vmx_check_nested_events() prior to re-entering the guest.

MTF currently works by virtue of KVM's hack that calls kvm_check_nested_events() from kvm_vcpu_running(), but that hack will be removed in the near future.  Until that call is removed, the patch introduces no functional change.

Fixes: 5ef8acbdd687 ("KVM: nVMX: Emulate MTF when performing instruction emulation") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson seanjc@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com

---

arch/x86/kvm/vmx/vmx.c | 6 ++++--  1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d7f8331d6f7e..940c0c0f8281 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1660,10 +1660,12 @@ static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu)          */         if (nested_cpu_has_mtf(vmcs12) &&             (!vcpu->arch.exception.pending || -            vcpu->arch.exception.nr == DB_VECTOR)) +            vcpu->arch.exception.nr == DB_VECTOR)) {                 vmx->nested.mtf_pending = true; -       else +               kvm_make_request(KVM_REQ_EVENT, vcpu); +       } else {                 vmx->nested.mtf_pending = false; +       }  }    static int vmx_skip_emulated_instruction(struct kvm_vcpu *vcpu)

Reviewed-by: Maxim Levitsky mlevitsk@redhat.com

Best regards, Maxim Levitsky