Re: [Xen-devel] Re: Still struggling with HVM: tx timeouts on emulated nics

[Stefan Bader <stefan.bader@xxxxxxxxxxxxx>]

On 06.10.2011 12:12, Stefano Stabellini wrote:
> On Wed, 5 Oct 2011, Stefan Bader wrote:
>> On 03.10.2011 19:24, Stefano Stabellini wrote:
>>> I am going to send a different patch upstream for Xen 4.2, because I
>>> would also like it to cover the very unlikely scenario in which a PV
>>> guest (like dom0 or a PV guest with PCI passthrough) is loosing level
>>> interrupts because when Xen tries to set the corresponding event channel
>>> pending the bit is alreay set. The codebase is different enough that
>>> making the same change on 4.1 is non-trivial. I am appending the new
>>> patch to this email, it would be great if you could test it. You just
>>> need a 4.2 hypervisor, not the entire system. You should be able to
>>> perform the test updating only xen.gz.
>>> If you have trouble if xen-unstable.hg tip, try changeset 23843.
>>
>> Hi Stefano,
>>
>> currently I would have the problem that I don't have too much time to move to
>> another hypervisor (tests may or may not be useful there with substantial
>> changes beside this one) with our next release being close.
>> But I think I got a usable backport of your change to 4.1.1 (you think it 
>> looks
>> ok?) and have given that a quick test which seems to be ok...
>> Though one drawback is that I don't have a setup which would use 
>> passthrough, so
>> that path is not tested. I think I did see (with a debugging version) that 
>> the
>> lost count was incremented and decremented in dom0, though.
>>
> 
> Honestly if you have to commit to a backport for your package right now,
> I would go for the previous version, because it is simpler and less
> likely to introduce regressions.

Agreed. Well at least I hope that since that backport seemed to fix the issue I
saw in 4.1.1 it will give some more confidence for you on the 4.2 version. With
the drawback of the passthrough not being tested.

-Stefan

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel