Re: [Bug #12465] KVM guests stalling on 2.6.28 (bisected)

Avi Kivity
2009-01-20T13:04:56Z

Kevin Shanahan wrote:
> On Tue, 2009-01-20 at 12:35 +0100, Ingo Molnar wrote:
>
>> * Kevin Shanahan <kmshanah-biM/RbsGxha6c6uEtOJ/EA@public.gmane.org> wrote:
>>
>>
>>> On Mon, 2009-01-19 at 22:45 +0100, Rafael J. Wysocki wrote:
>>>
>>>> This message has been generated automatically as a part of a report
>>>> of regressions introduced between 2.6.27 and 2.6.28.
>>>>
>>>> The following bug entry is on the current list of known regressions
>>>> introduced between 2.6.27 and 2.6.28. Please verify if it still should
>>>> be listed and let me know (either way).
>>>>
>>>>
>>>> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=12465
>>>> Subject : KVM guests stalling on 2.6.28 (bisected)
>>>> Submitter : Kevin Shanahan <kmshanah-biM/RbsGxha6c6uEtOJ/EA@public.gmane.org>
>>>> Date : 2009-01-17 03:37 (3 days old)
>>>>
>>> Yes, please keep this on the list.
>>>
>> This only seems to occur under KVM, right? I.e. you tested it with -no-kvm
>> and the problem went away, correct?
>>
>
> Well, the I couldn't make the test conditions identical, but it the
> problem didn't occur with the test I was able to do:
>
> http://marc.info/?l=linux-kernel&m=123228728416498&w=2
>
>

Can you also try with -no-kvm-irqchip?

You will need to comment out the lines

/* ISA IRQs map to GSI 1-1 except for IRQ0 which maps
* to GSI 2. GSI maps to ioapic 1-1. This is not
* the cleanest way of doing it but it should work. */

if (vector == 0)
vector = 2;

in qemu/hw/apic.c (should also fix -no-kvm smp). This will change kvm
wakeups to use signals rather than the in-kernel code, which may be buggy.

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