If pit delivers interrupt while pic is masking it OS will never do EOI and ack notifier will not be called so when pit will be unmasked no pit interrupts will be delivered any more. Calling mask notifiers solves this issue. Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx> diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index 819b748..80d98cd 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -363,10 +363,18 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val) } } else switch (s->init_state) { - case 0: /* normal mode */ + case 0: { /* normal mode */ + u8 imr_diff = s->imr ^ val; s->imr = val; + for (irq = 0; irq < PIC_NUM_PINS/2; irq++) + if (imr_diff & (1 << irq)) + kvm_fire_mask_notifiers( + s->pics_state->kvm, + SELECT_PIC(irq), irq, + !!(s->imr & (1 << irq))); pic_update_irq(s->pics_state); break; + } case 1: s->irq_base = val & 0xf8; s->init_state = 2; -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html