On 2022/5/16 21:58, Sean Christopherson wrote:
On Mon, May 16, 2022, Yanfei Xu wrote:
When kernel handles the vm-exit caused by external interrupts and PMI,
it always set a type of kvm_intr_type to handling_intr_from_guest to
tell if it's dealing an IRQ or NMI.
However, the further type judgment is missing in kvm_arch_pmi_in_guest().
It could make the PMI of intel_pt wrongly considered it comes from a
guest once the PMI breaks the handling of vm-exit of external interrupts.
Fixes: db215756ae59 ("KVM: x86: More precisely identify NMI from guest when handling PMI")
Signed-off-by: Yanfei Xu <yanfei.xu@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 8 +++++++-
arch/x86/kvm/x86.h | 6 ------
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 4ff36610af6a..308cf19f123d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1582,8 +1582,14 @@ static inline int kvm_arch_flush_remote_tlb(struct kvm *kvm)
return -ENOTSUPP;
}
+enum kvm_intr_type {
+ /* Values are arbitrary, but must be non-zero. */
+ KVM_HANDLING_IRQ = 1,
+ KVM_HANDLING_NMI,
+};
+
#define kvm_arch_pmi_in_guest(vcpu) \
- ((vcpu) && (vcpu)->arch.handling_intr_from_guest)
+ ((vcpu) && (vcpu)->arch.handling_intr_from_guest == KVM_HANDLING_NMI)
My understanding is that this isn't correct as a general change, as perf events
can use regular IRQs in some cases. See commit dd60d217062f4 ("KVM: x86: Fix perf
timer mode IP reporting").
I assume there's got to be a way to know which mode perf is using, e.g. we should
be able to make this look something like:
((vcpu) && (vcpu)->arch.handling_intr_from_guest == kvm_pmi_vector)
Thanks for your comments, I am going to understand these clearly and
then reply or give a next version.
Regards,
Yanfei
void kvm_mmu_x86_module_init(void);
int kvm_mmu_vendor_module_init(void);
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index 588792f00334..3bdf1bc76863 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -344,12 +344,6 @@ static inline bool kvm_cstate_in_guest(struct kvm *kvm)
return kvm->arch.cstate_in_guest;
}
-enum kvm_intr_type {
- /* Values are arbitrary, but must be non-zero. */
- KVM_HANDLING_IRQ = 1,
- KVM_HANDLING_NMI,
-};
-
static inline void kvm_before_interrupt(struct kvm_vcpu *vcpu,
enum kvm_intr_type intr)
{
--
2.32.0
