The patch below does not apply to the 6.0-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Possible dependencies:

2ea89c7f7f7b ("KVM: nVMX: Make an event request when pending an MTF nested VM-Exit") 7709aba8f716 ("KVM: x86: Morph pending exceptions to pending VM-Exits at queue time") 28360f887068 ("KVM: x86: Evaluate ability to inject SMI/NMI/IRQ after potential VM-Exit") 6c593b5276e6 ("KVM: x86: Hoist nested event checks above event injection logic") 72c14e00bdc4 ("KVM: x86: Formalize blocking of nested pending exceptions") d4963e319f1f ("KVM: x86: Make kvm_queued_exception a properly named, visible struct") 593a5c2e3c12 ("KVM: nVMX: Unconditionally clear mtf_pending on nested VM-Exit") 5623f751bd9c ("KVM: x86: Treat #DBs from the emulator as fault-like (code and DR7.GD=1)") b9d44f9091ac ("KVM: nVMX: Prioritize TSS T-flag #DBs over Monitor Trap Flag") 8d178f460772 ("KVM: nVMX: Treat General Detect #DB (DR7.GD=1) as fault-like") eba9799b5a6e ("KVM: VMX: Drop bits 31:16 when shoving exception error code into VMCS")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 2ea89c7f7f7b192e32d1842dafc2e972cd14329b Mon Sep 17 00:00:00 2001 From: Sean Christopherson seanjc@google.com Date: Wed, 21 Sep 2022 00:31:51 +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. Until that call is removed, the patch introduces no real functional change.

Fixes: 5ef8acbdd687 ("KVM: nVMX: Emulate MTF when performing instruction emulation") Cc: stable@vger.kernel.org Reviewed-by: Maxim Levitsky mlevitsk@redhat.com Signed-off-by: Sean Christopherson seanjc@google.com Message-Id: 20220921003201.1441511-3-seanjc@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 85318d803f4f..3a080051a4ec 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -6632,6 +6632,9 @@ 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: diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 94c314dc2393..9dba04b6b019 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -1665,10 +1665,12 @@ static void vmx_update_emulated_instruction(struct kvm_vcpu *vcpu) (!vcpu->arch.exception.pending || vcpu->arch.exception.vector == DB_VECTOR) && (!vcpu->arch.exception_vmexit.pending || - vcpu->arch.exception_vmexit.vector == DB_VECTOR)) + vcpu->arch.exception_vmexit.vector == 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)