[libvirt] xen/libvirt freeze while attching network-device to vm´s - question about provided patches

[Jim Fehlig]

On 09/09/2016 09:43 AM, Andrea Bolognani wrote:
> On Thu, 2016-09-08 at 14:04 +0000, Guido.Rossmueller at gdata.de wrote:
>> Hello everybody,
>>
>> a colleague of me described last november a problem that we have with libvirt and xen
>>
>> https://www.redhat.com/archives/libvir-list/2015-November/msg00130.html
>>
>> Jim Fehlig provided for this problem a patch a few days later:
>>
>> https://www.redhat.com/archives/libvir-list/2015-November/msg00520.html
>>
>> The provided patch work great and we have no problems until we applied them..
>>
>> Now we a in the situation that we want to migrate to libvirt 2.1, and we saw the same
>> problem that we have last year, again.
>> After we take a look in the source code, we determine that the patches are didn´t go
>> in the source code. So we modify the patches in that way, that we could apply them
>> again, and all looks good.
>>
>> My question, is their any special reason why this patches didn´t go in the source code?
>>
>> I see same posts on the maillinglist, but absolute statement for or again the patches
>> from Jim Fehlig.
> Jim said he would submit a v2 to address some concerns raised during
> review[1]; later, he reported some issues he'd run into[2] while
> working on it.

I had planned to wait a few days to see if Ian had any thoughts on the libxl
side. I'm not familiar with the code and would need some time to understand it
before debugging further. But I've never got back to that work :-(.

>
> So it looks to me like the code was not yet ready for merge, which
> would explain it being tagged as RFC. And then it probably just
> slipped through the cracks :)

Sort of. It is an item that is fermenting on my todo list.

>
> CCing Jim for insights on the current status of the patch.

I still have a branch in my local git tree :-). It needs rebased and tested
against Xen 4.7 (and probably xen.git master).

>
>
> [1] https://www.redhat.com/archives/libvir-list/2015-November/msg00958.html
> [2] https://www.redhat.com/archives/libvir-list/2015-November/msg00974.html

Guido,

With the rebased version of the patch, do you notice the issue described in [2]
during your testing? To trigger it, I used a hacky script that created,
shutdown, destroyed, saved, and restored many domains in parallel.

What version of Xen are you using?

Regards,
Jim