diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2012-07-19 13:45:20 +0300 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2012-07-20 16:12:00 -0300 |
| commit | 1a577b72475d161b6677c05abe57301362023bb2 (patch) | |
| tree | d8a9910f0016ada479c5a88c1a330b5e1cbc7ef1 /virt/kvm/ioapic.h | |
| parent | d63d3e6217c49b81d74141b7920bbe5950532432 (diff) | |
| download | lwn-1a577b72475d161b6677c05abe57301362023bb2.tar.gz lwn-1a577b72475d161b6677c05abe57301362023bb2.zip | |
KVM: fix race with level interrupts
When more than 1 source id is in use for the same GSI, we have the
following race related to handling irq_states race:
CPU 0 clears bit 0. CPU 0 read irq_state as 0. CPU 1 sets level to 1.
CPU 1 calls kvm_ioapic_set_irq(1). CPU 0 calls kvm_ioapic_set_irq(0).
Now ioapic thinks the level is 0 but irq_state is not 0.
Fix by performing all irq_states bitmap handling under pic/ioapic lock.
This also removes the need for atomics with irq_states handling.
Reported-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'virt/kvm/ioapic.h')
| -rw-r--r-- | virt/kvm/ioapic.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/virt/kvm/ioapic.h b/virt/kvm/ioapic.h index 32872a09b63f..a30abfe6ed16 100644 --- a/virt/kvm/ioapic.h +++ b/virt/kvm/ioapic.h @@ -74,7 +74,9 @@ void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode); bool kvm_ioapic_handles_vector(struct kvm *kvm, int vector); int kvm_ioapic_init(struct kvm *kvm); void kvm_ioapic_destroy(struct kvm *kvm); -int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level); +int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int irq_source_id, + int level); +void kvm_ioapic_clear_all(struct kvm_ioapic *ioapic, int irq_source_id); void kvm_ioapic_reset(struct kvm_ioapic *ioapic); int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src, struct kvm_lapic_irq *irq); |