Re: [regression] KVM: hangs and "irq timeout" booting HURD unless -no-kvm-irqchip passed

[Avi Kivity <avi@redhat.com>]

On 02/08/2011 04:47 PM, Gleb Natapov wrote:
> On Tue, Feb 08, 2011 at 04:43:33PM +0200, Avi Kivity wrote:
> >  On 02/08/2011 04:22 PM, Marcelo Tosatti wrote:
> >  >I don't think the isr_ack logic is overly complex that it should be
> >  >removed. For some cases it is still beneficial, see example case on
> >  >commit e48258009d941, which is not handled by kick coalescing of
> >  >kvm_vcpu_kick.
> >
> >  On the other hand, I think it can be done differently.  For example
> >  LVT0 is probably programmed to mask interrupts; we can simply look
> >  at it and not kick if that's the case.  We can use notifiers from
> >  the lapic to the pic to avoid looking at lapic data.
> >
> I believe this is what my patch is doing. Look at pic_unlock(). The code
> search for vcpu to kick by calling kvm_apic_accept_pic_intr() function
> (which checks that LVT is masked).

It does indeed.

> If no vcpu is found we kicks bsp.
> Why? I removed that.

The code that looks for a vcpu that has LVT0 unmasked is newer than the 
isr_ack code (see cfe149e91b82).  So it looks like the isr_ack code is 
indeed unnecessary now.

-- 
error compiling committee.c: too many arguments to function