[PATCH v2 9/9] KVM: SVM: Reenable handle_fastpath_set_msr_irqoff() after complete_interrupts()

From: Wanpeng Li
Date: Thu Sep 10 2020 - 05:54:55 EST


From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

Moving the call to svm_exit_handlers_fastpath() after svm_complete_interrupts()
since svm_complete_interrupts() consumes rip and reenable the function
handle_fastpath_set_msr_irqoff() call in svm_exit_handlers_fastpath().

Suggested-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Cc: Paul K. <kronenpj@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index dafc14d..b3e3429 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -3347,6 +3347,10 @@ static void svm_cancel_injection(struct kvm_vcpu *vcpu)

static fastpath_t svm_exit_handlers_fastpath(struct kvm_vcpu *vcpu)
{
+ if (to_svm(vcpu)->vmcb->control.exit_code == SVM_EXIT_MSR &&
+ to_svm(vcpu)->vmcb->control.exit_info_1)
+ return handle_fastpath_set_msr_irqoff(vcpu);
+
return EXIT_FASTPATH_NONE;
}

@@ -3495,7 +3499,6 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)
stgi();

/* Any pending NMI will happen here */
- exit_fastpath = svm_exit_handlers_fastpath(vcpu);

if (unlikely(svm->vmcb->control.exit_code == SVM_EXIT_NMI))
kvm_after_interrupt(&svm->vcpu);
@@ -3530,6 +3533,12 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu)

svm_complete_interrupts(svm);
vmcb_mark_all_clean(svm->vmcb);
+
+ if (is_guest_mode(vcpu))
+ return EXIT_FASTPATH_NONE;
+
+ exit_fastpath = svm_exit_handlers_fastpath(vcpu);
+
return exit_fastpath;
}

--
2.7.4