diff options
| author | Adamos Ttofari <attofari@amazon.de> | 2022-12-08 12:44:14 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-12-23 20:07:40 +0300 |
| commit | fceb3a36c29a957515d5156e5e7844ea040dc43d (patch) | |
| tree | e5f20fab23470fc653c39d6fc6115bdd95a42a50 /arch | |
| parent | 55c590adfe18b5380f7c4ae3696468bc5c916ee5 (diff) | |
| download | linux-fceb3a36c29a957515d5156e5e7844ea040dc43d.tar.xz | |
KVM: x86: ioapic: Fix level-triggered EOI and userspace I/OAPIC reconfigure race
When scanning userspace I/OAPIC entries, intercept EOI for level-triggered
IRQs if the current vCPU has a pending and/or in-service IRQ for the
vector in its local API, even if the vCPU doesn't match the new entry's
destination. This fixes a race between userspace I/OAPIC reconfiguration
and IRQ delivery that results in the vector's bit being left set in the
remote IRR due to the eventual EOI not being forwarded to the userspace
I/OAPIC.
Commit 0fc5a36dd6b3 ("KVM: x86: ioapic: Fix level-triggered EOI and IOAPIC
reconfigure race") fixed the in-kernel IOAPIC, but not the userspace
IOAPIC configuration, which has a similar race.
Fixes: 0fc5a36dd6b3 ("KVM: x86: ioapic: Fix level-triggered EOI and IOAPIC reconfigure race")
Signed-off-by: Adamos Ttofari <attofari@amazon.de>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20221208094415.12723-1-attofari@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/irq_comm.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kvm/irq_comm.c b/arch/x86/kvm/irq_comm.c index 0687162c4f22..3742d9adacfc 100644 --- a/arch/x86/kvm/irq_comm.c +++ b/arch/x86/kvm/irq_comm.c @@ -426,8 +426,9 @@ void kvm_scan_ioapic_routes(struct kvm_vcpu *vcpu, kvm_set_msi_irq(vcpu->kvm, entry, &irq); if (irq.trig_mode && - kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT, - irq.dest_id, irq.dest_mode)) + (kvm_apic_match_dest(vcpu, NULL, APIC_DEST_NOSHORT, + irq.dest_id, irq.dest_mode) || + kvm_apic_pending_eoi(vcpu, irq.vector))) __set_bit(irq.vector, ioapic_handled_vectors); } } |