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

[Peter Lieven <pl@dlhnet.de>]

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
>