Re: NetBSD dom0 PVH: hardware interrupts stalls

[Manuel Bouyer <bouyer@xxxxxxxxxxxxxxx>]

On Fri, Nov 20, 2020 at 09:28:55AM +0100, Roger Pau Monné wrote:
> > i.e. at that point we're waiting for Dom0 to signal it's done handling
> > the IRQ. There is, however, a timer associated with this. Yet that's
> > actually to prevent the system getting stuck, i.e. the "in-flight"
> > state ought to clear 1ms later (when that timer expires), and hence
> > ought to be pretty unlikely to catch when non-zero _and_ something's
> > actually stuck.
> 
> I somehow assumed the interrupt was in-flight because the printing to
> the Xen console caused one to be injected, and thus dom0 didn't had
> time to Ack it yet.

What does Xen consider to be an ACK from the dom0 ?
AFAIK we have EOI only for LAPIC interrupts.

-- 
Manuel Bouyer <bouyer@xxxxxxxxxxxxxxx>
     NetBSD: 26 ans d'experience feront toujours la difference
--