diff options
| author | Sean Christopherson <seanjc@google.com> | 2025-02-22 09:47:46 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2025-03-14 14:20:55 -0400 |
| commit | 14aecf2a5bc3418bfb760ee9e45ddbc12480ebca (patch) | |
| tree | 20152948ff7889a966250645eb38055a8733f6cc | |
| parent | 24c12911160e47700f9c96cea95770f0300682f4 (diff) | |
KVM: x86: Assume timer IRQ was injected if APIC state is protected
If APIC state is protected, i.e. the vCPU is a TDX guest, assume a timer
IRQ was injected when deciding whether or not to busy wait in the "timer
advanced" path. The "real" vIRR is not readable/writable, so trying to
query for a pending timer IRQ will return garbage.
Note, TDX can scour the PIR if it wants to be more precise and skip the
"wait" call entirely.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Binbin Wu <binbin.wu@linux.intel.com>
Message-ID: <20250222014757.897978-6-binbin.wu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/lapic.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index bbdede07d063..e78b1d223230 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1797,8 +1797,17 @@ static void apic_update_lvtt(struct kvm_lapic *apic) static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; - u32 reg = kvm_lapic_get_reg(apic, APIC_LVTT); + u32 reg; + /* + * Assume a timer IRQ was "injected" if the APIC is protected. KVM's + * copy of the vIRR is bogus, it's the responsibility of the caller to + * precisely check whether or not a timer IRQ is pending. + */ + if (apic->guest_apic_protected) + return true; + + reg = kvm_lapic_get_reg(apic, APIC_LVTT); if (kvm_apic_hw_enabled(apic)) { int vec = reg & APIC_VECTOR_MASK; void *bitmap = apic->regs + APIC_ISR; |