[PATCH 3/4] drm/virtio: remove drm_dev_set_unique workaround

[Emil Velikov]

Hi Laszlo,

On 28 March 2018 at 11:27, Laszlo Ersek <lersek at redhat.com> wrote:
> On 03/28/18 03:24, Emil Velikov wrote:
>> From: Emil Velikov <emil.velikov at collabora.com>
>>
>> Ealier commit a325725633c26aa66ab940f762a6b0778edf76c0 did not attribute
>> that virtio can be either PCI or a platform device and removed the
>> .set_busid hook. Whereas only the "platform" instance should have been
>> removed.
>>
>> Since then, two things have happened:
>>  - the driver manually calls drm_dev_set_unique, addressing the Xserver
>> regression - see commit 9785b4321b0bd701f8d21d3d3c676a7739a5cf22
>>  - core itself calls drm_pci_set_busid, on drm_set_busid IOCTL setting
>> the busid, so we don't need to fallback to dev->unique - see commit
>> 5c484cee7ef9c4fd29fa0ba09640d55960977145
>>
>> With that in place we can remove the local workaround.
>>
>> Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
>> Cc: Gerd Hoffmann <kraxel at redhat.com>
>> Cc: Hans de Goede <hdegoede at redhat.com>
>> Cc: Laszlo Ersek <lersek at redhat.com>
>> Signed-off-by: Emil Velikov <emil.velikov at collabora.com>
>> ---
>> Gents, can someone double-check this please? Just in case.
>
> I guess I should test whether this series regresses the use case
> described in c2cbc38b97; is that correct?
>
Precisely.

> I can add that to my todo list, but it won't be quick. I get into
> building kernels maybe once per quarter :)
>
> What repo and branch should I apply this series on top of? ... Actually,
> I was only CC'd on patch 3/4, so I don't even have the full series. Do
> you have a public branch somewhere?
>
In practise only 3/4 is needed applied on top of any tree that has the
commits mentioned in the summary.

FWIW here is a patchwork series [1], just this patch [2] and a tree [3].

[1] https://patchwork.freedesktop.org/series/40778/
[2] https://patchwork.freedesktop.org/patch/213335/
[3] https://github.com/evelikov/linux/commits/ioctl-cleanups

> (If this would mean too much work for you, esp. considering that I'm
> going to be slow, feel free to go ahead with the patch. Should I find
> later that something broke, I'll whine then. :) )
>
The original patch that caused breakage was tested, yet seemingly in a
different manner.
Hence, I'd love it, if anyone who had the original problem can can
give this a try.

I guess it can wait 1-2 weeks before getting merged, since it won't
cause any conflicts ;-)

Thanks!
Emil