On Tue, Jan 24, 2012 at 02:44:15PM +0100, Jan Kiszka wrote: > On 2012-01-24 14:06, Gleb Natapov wrote: > > The spec says that during initialization "The edge sense circuit is > > reset which means that following initialization an interrupt request > > (IR) input must make a low-to-high transition to generate an interrupt", > > but currently if edge triggered interrupt is in IRR it is delivered > > after i8259 initialization. > > > > Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx> > > diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c > > index b6a7353..81cf4fa 100644 > > --- a/arch/x86/kvm/i8259.c > > +++ b/arch/x86/kvm/i8259.c > > @@ -307,6 +307,7 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val) > > if (val & 0x10) { > > s->init4 = val & 1; > > s->last_irr = 0; > > + s->irr &= s->elcr; > > Does & elcr make a relevant difference? QEMU simply sets irr to 0. If > that's an issue, we need to fix both. > I saw what QEMU does. It's hard to tell looking at the spec what's more correct. I think by zeroing irr we may lose level triggered interrupts that happened just before init. -- 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