On Fri, Apr 29, 2022, Paolo Bonzini wrote:
On 4/29/22 19:03, Sean Christopherson wrote:
This doesn't even compile...
arch/x86/kvm/vmx/nested.c: In function ‘vmx_has_nested_events’: arch/x86/kvm/vmx/nested.c:3862:61: error: ‘vmx’ undeclared (first use in this function) 3862 | return nested_vmx_preemption_timer_pending(vcpu) || vmx->nested.mtf_pending; | ^~~ arch/x86/kvm/vmx/nested.c:3862:61: note: each undeclared identifier is reported only once for each function it appears in CC [M] arch/x86/kvm/svm/svm_onhyperv.o arch/x86/kvm/vmx/nested.c:3863:1: error: control reaches end of non-void function [-Werror=return-type] 3863 | } | ^ cc1: all warnings being treated as errors LD [M] arch/x86/kvm/kvm.o
Yeah, it doesn't. Of course this will need a v2, also because there are failures in the vmx tests.
Heh, I suspected there would be failures, I was about to type up a response to patch 3. MTF is subtly relying on the call from kvm_vcpu_running() to inject the event.
From: Sean Christopherson seanjc@google.com Date: Fri, 29 Apr 2022 17:30:54 +0000 Subject: [PATCH] KVM: nVMX: Make an event request when pending an MTF nested VM-Exit
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.
Fixes: 5ef8acbdd687 ("KVM: nVMX: Emulate MTF when performing instruction emulation") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson seanjc@google.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 d58b763df855..4c635bc08105 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1577,10 +1577,12 @@ 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)
base-commit: 39aa5903e8c407e5128c15aeabb0717b275b007e --