diff options
| author | Wanpeng Li <kernellwpQ@gmail.com> | 2020-09-12 02:16:39 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-09-12 02:19:23 -0400 |
| commit | e42c68281b444f9a20d72a062f8c6fd0d31e4de8 (patch) | |
| tree | 67741349b8710c32ef6367662ed7eb062955826f | |
| parent | d831de177217cd494bfb99f2c849a0d40c2a7890 (diff) | |
KVM: SVM: avoid emulation with stale next_rip
svm->next_rip is reset in svm_vcpu_run() only after calling
svm_exit_handlers_fastpath(), which will cause SVM's
skip_emulated_instruction() to write a stale RIP.
We can move svm_exit_handlers_fastpath towards the end of
svm_vcpu_run(). To align VMX with SVM, keep svm_complete_interrupts()
close as well.
Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Paul K. <kronenpj@kronenpj.dyndns.org>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
[Also move vmcb_mark_all_clean before any possible write to the VMCB.
- Paolo]
| -rw-r--r-- | arch/x86/kvm/svm/svm.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 03dd7bac8034..8ba4a32843fa 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -2938,8 +2938,6 @@ static int handle_exit(struct kvm_vcpu *vcpu, fastpath_t exit_fastpath) if (npt_enabled) vcpu->arch.cr3 = svm->vmcb->save.cr3; - svm_complete_interrupts(svm); - if (is_guest_mode(vcpu)) { int vmexit; @@ -3504,7 +3502,6 @@ 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); @@ -3518,6 +3515,7 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu) } svm->vmcb->control.tlb_ctl = TLB_CONTROL_DO_NOTHING; + vmcb_mark_all_clean(svm->vmcb); /* if exit due to PF check for async PF */ if (svm->vmcb->control.exit_code == SVM_EXIT_EXCP_BASE + PF_VECTOR) @@ -3537,7 +3535,8 @@ static __no_kcsan fastpath_t svm_vcpu_run(struct kvm_vcpu *vcpu) SVM_EXIT_EXCP_BASE + MC_VECTOR)) svm_handle_mce(svm); - vmcb_mark_all_clean(svm->vmcb); + svm_complete_interrupts(svm); + exit_fastpath = svm_exit_handlers_fastpath(vcpu); return exit_fastpath; } |