On 8/2/22 19:20, Claudio Fontana wrote:
> On 8/2/22 03:40, Stephen Hemminger wrote:
>> On Tue, 2 Aug 2022 02:49:36 +0200
>> Claudio Fontana <cfont...@suse.de> wrote:
>>
>>> This is an alternative, more general fix compared with PATCH v1,
>>> and fixes style issues in v2.
>>>
>>> The series fixes a segmentation fault in the OVS PMD thread when
>>> resynchronizing with QEMU after the guest application has been killed
>>> with SIGKILL (patch 1/2),
>>>
>>> The segmentation fault can be caused by the guest DPDK application,
>>> which is able this way to crash the OVS process on the host,
>>> see the backtrace in patch 1/2.
>>>
>>> Patch 2/2 is an additional improvement in the current error handling.
>>
>> Checking for NULL and 0 is good on host side.
>> But guest should probably not be sending such a useless request?
>
>
> Right, I focused on hardening the host side, as that is what the customer
> required.
>
> This happens specifically when the guest application goes away abruptly and
> has no chance to signal anything (SIGKILL),
> and at restart issues a virtio reset on the device, which in qemu causes also
> a (actually two) virtio_net set_status, which attempt to stop the queues
> (twice).
>
> DPDK seems to think at that point that it needs to drain the queue, and tries
> to process MAX_PKT_BURST buffers
> ("about to dequeue 32 buffers"),
>
> then calls fill_vec_buf_split and gets absolutely nothing.
>
> I think this should also address the reports in this thread:
>
> https://inbox.dpdk.org/dev/sa1pr08mb713373b0d19329c38c7527bb83...@sa1pr08mb7133.namprd08.prod.outlook.com/
>
> in addition to my specific customer request,
>
> Thanks,
>
> Claudio
anything more required from my side? Do you need a respin without the
"Tested-by" tag?
Thanks,
Claudio
