Re: [Patch v1] x86: Fix the logical destination mode test

Nitesh Narayan Lal
2020-04-14T16:27:41Z

On 4/14/20 12:11 PM, Vitaly Kuznetsov wrote:
> Nitesh Narayan Lal <nitesh@redhat.com> writes:
>
>> On 4/14/20 11:30 AM, Vitaly Kuznetsov wrote:
>>> Nitesh Narayan Lal <nitesh@redhat.com> writes:
>>>
>>>> On 4/14/20 10:01 AM, Vitaly Kuznetsov wrote:
>>>>> Also, this patch could've been split.
>>>> I can divide it 2 parts:
>>>> 1. support for logical destination mode.
>>>> 2. support for physical destination mode. I can also fix  the above issue in
>>>> this patch itself.
>>>> Does that make sense?
>>> Too late, it's already commited :-) I just meant to say that
>>> e.g. spinlock part could've been split into its own patch, unittests.cfg
>>> - another one,...
>> Ah, I see. I will be more careful.
>> For now,  I will just move the physical destination mode test back under
>> the check. Will that be acceptable as a standalone patch?
> This is already in Paolo's patch:
> https://lore.kernel.org/kvm/87zhbexh3v.fsf@vitty.brq.redhat.com/T/#m9791cd50a9d82fabdaddcb9259d14df3b89ed250

Yeap, this patch is already in the tree.
I was referring to a new patch in which I would move the physical destination
mode test
under 'if (cpu_count() > 1)', that should fixed the ioapic-split hang.
Sorry about the confusion.

>
>> In between I have a question is it normal for test_ioapic_self_reconfigure()
>> to fail when executed with irqchip split?
>> If so do we expect that it will leave the VM in some sort of dirty state
>> that causes the following test to fail?
> Not sure I got your question but IMO when someone does
> ./run_tests.sh
> all tests are supposed to pass -- unless there is a bug in KVM (e.g. the
> person is running an old kernel). In case we're seeing failures (or,
> even worse, hangs) with the latest upstream kernel -- something is
> broken, either KVM or kvm-unit-tests.

Yeap, I am not sure what is the exact issue that causes
test_ioapic_self_reconfigure() to
fail when used with kernel_irqchip=split.
I can again take a look to find out the root cause later.

--
Nitesh