Re: [Qemu-devel] qemu-kvm-1.0.1 - unable to exit if vcpu is in infinite loop

[Peter Lieven]

On 02.07.2012 09:05, Jan Kiszka wrote:
> On 2012-07-01 21:18, Peter Lieven wrote:
> > Am 01.07.2012 um 10:19 schrieb Avi Kivity:
> >
> > > On 06/28/2012 10:27 PM, Peter Lieven wrote:
> > > > Am 28.06.2012 um 18:32 schrieb Avi Kivity:
> > > >
> > > > > On 06/28/2012 07:29 PM, Peter Lieven wrote:
> > > > > > > Yes. A signal is sent, and KVM returns from the guest to userspace on
> > > > > > > pending signals.
> > > > > > is there a description available how this process exactly works?
> > > > > The kernel part is in vcpu_enter_guest(), see the check for
> > > > > signal_pending().  But this hasn't seen changes for quite a long while.
> > > > Thank you, i will have a look. I noticed a few patches that where submitted
> > > > during the last year, maybe one of them is related:
> > > >
> > > > Switch SIG_IPI to SIGUSR1
> > > > Fix signal handling of SIG_IPI when io-thread is enabled
> > > >
> > > > In the first commit there is mentioned a "32-on-64-bit Linux kernel bug"
> > > > is there any reference to that?
> > >
> > > http://web.archiveorange.com/archive/v/1XS1vwGSFLyYygwTXg1K.  Are you
> > > running 32-on-64?
> > I think the issue occurs when running a 32-bit guest on a 64-bit system. Afaik, 
> > the
> > isolinux loader where is see the race is 32-bit altough it is a 64-bit ubuntu 
> > lts
> > cd image. The second case where i have seen the race is on shutdown of a
> > Windows 2000 Server which is also 32-bit.
> "32-on-64" particularly means using a 32-bit QEMU[-kvm] binary on a
> 64-bit host kernel. What does "file qemu-system-x86_64" report about yours?
Its custom build on a 64-bit linux as 64-bit application. I will try to 
continue to find out
today whats going wrong. Any help or hints appreciated ;-)

Thanks,
Peter

> Jan