Re: [BUG] win2008 guest cannot get ip through sriov

[Julien Grall <julien.grall@linaro.org>]

On 09/11/17 14:36, Julien Grall wrote:
> Hi Roger,
> 
> On 09/11/17 09:27, Roger Pau Monné wrote:
>> On Thu, Nov 09, 2017 at 12:22:49AM +0000, Hao, Xudong wrote:
>>>> Qemu-xen didn't have commit a80363, so I report this issue to ask 
>>>> for sync up
>>>> with qemu upstream. Last mail I mean I usually used Qemu Xen tree to 
>>>> do test,
>>>> and found out this issue.
>>>>
>>>> Before requesting the backport, have you tested whether it fixes 
>>>> your issues?
>>>>
>>>
>>> Yes, Luwei (Cced) tested it with pass result.
>>
>> In which case requesting a backport would be in place on the grounds
>> that's a bug fix.
>>
>> The patch in question fixes a bug mostly seen when doing
>> PCI-passthrough of devices that support MSI-X interrupts to Windows
>> guest (and Windows attempts to setup the interrupts using MSI-X). It
>> doesn't manifest on Linux or FreeBSD because these OSes use a
>> different dance to setup MSI-X interrupts, and thus are not affected.
>> It's likely that other OSes with different MSI-X implementations are
>> able to trigger that bug. The result of not having the patch is that
>> interrupts of passed through devices will stay masked, thus
>> preventing the device from working (unless polling mode only is
>> used).
>>
>> Pros:
>>   - It fixes a bug.
>>   - The patch is not very big or intrusive.
>>
>> Cons:
>>   - It hasn't been tested as it's not in qemu-xen.
>>   - Only Windows is affected by the bug AFAIK.
>>
>> IMHO, iff the backport is accepted it should be performed ASAP, so
>> that the patch can be properly tested before the release.
> 
> Thank you for the detailed explanation :). On a previous e-mail Stefano 
> were happy with the backport. So:
> 
> Release-acked-by: Julien Grall <julien.grall@linaro.org>

Note that I think we would need to update xen also to point to the 
commit with this backport included.

Cheers,

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel