On 8/22/22 19:52, Jim Mattson wrote:
On Mon, Aug 22, 2022 at 10:08 AM Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
From: Sean Christopherson <seanjc@xxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
What happens if live migration occurs before the KVM_REQ_EVENT is processed?
Good point, this must be squashed in:
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index ab135f9ef52f..a703b71d675d 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -6481,6 +6481,8 @@ static int vmx_set_nested_state(struct kvm_vcpu *vcpu,
if (ret)
goto error_guest_mode;
+ if (vmx->nested.mtf_pending)
+ kvm_make_request(KVM_REQ_EVENT, vcpu);
return 0;
error_guest_mode:
so that the other side restores the request.
Paolo
