KVM: nVMX: Fix nested vmexit ack intr before load vmcs01

An external interrupt will cause a vmexit with reason "external interrupt"
when L2 is running.  L1 will pick up the interrupt through vmcs12 if
L1 set the ack interrupt bit.  Commit 77b0f5d (KVM: nVMX: Ack and write
vector info to intr_info if L1 asks us to) retrieves the interrupt that
belongs to L1 before vmcs01 is loaded.

This will lead to problems in the next patch, which would write to SVI
of vmcs02 instead of vmcs01 (SVI of vmcs02 doesn't make sense because
L2 runs without APICv).

Reviewed-by: Paolo Bonzini <[email protected]>
Tested-by: Liu, RongrongX <[email protected]>
Tested-by: Felipe Reyes <[email protected]>
Fixes: 77b0f5d67ff2781f36831cba79674c3e97bd7acf
Cc: [email protected]
Signed-off-by: Wanpeng Li <[email protected]>
[Move tracepoint as well. - Paolo]
Signed-off-by: Paolo Bonzini <[email protected]>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e618f34bde2d795a8a86b4072df085b781d982ac..bfe11cf124a1ea26cfa8513ceac83d450e13c7ef 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -8754,6 +8754,8 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason,
        prepare_vmcs12(vcpu, vmcs12, exit_reason, exit_intr_info,
                       exit_qualification);
 
+       vmx_load_vmcs01(vcpu);
+
        if ((exit_reason == EXIT_REASON_EXTERNAL_INTERRUPT)
            && nested_exit_intr_ack_set(vcpu)) {
                int irq = kvm_cpu_get_interrupt(vcpu);
@@ -8769,8 +8771,6 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason,
                                       vmcs12->vm_exit_intr_error_code,
                                       KVM_ISA_VMX);
 
-       vmx_load_vmcs01(vcpu);
-
        vm_entry_controls_init(vmx, vmcs_read32(VM_ENTRY_CONTROLS));
        vm_exit_controls_init(vmx, vmcs_read32(VM_EXIT_CONTROLS));
        vmx_segment_cache_clear(vmx);