Regression: drm: Lobotomize set_busid nonsense for !pci drivers (a325725633c2)

[Hans de Goede]

Hi,

On 30-09-16 16:51, Laszlo Ersek wrote:
> On 09/30/16 12:35, Hans de Goede wrote:
>
>> Attached are 2 patches against the xserver which should fix this,
>> please give them a try.
>
> Sorry about the delay.
>
> The patches don't seem to fix the issue for me. Please see the Xorg log
> attached.
>
> I tested the patches as follows. Given that my bisection had been done
> in a Fedora 24 guest, using
>
>   xorg-x11-server-1.18.4-4.fc24
>   http://koji.fedoraproject.org/koji/buildinfo?buildID=794494
>
> I now rebuilt the guest kernel exactly at the failing commit (a325725
> "drm: Lobotomize set_busid nonsense for !pci drivers"), and first
> reproduced the issue with the above X server.
>
> Then, I ported your patches to "xorg-server-1.18.4" (using the upstream
> xserver tree), and rebuilt the Fedora package with the backport. For the
> backport, I had to cherry-pick the following two patches from master first:
>
> 1 ca8d88e50310 xfree86: recognize primary BUS_PCI device in
>                xf86IsPrimaryPlatform()
> 2 ea91db4b8331 config: fix GPUDevice fail when AutoAddGPU off + BusID
>
> This way your patches applied cleanly. (Cherry pick #1 above is actually
> necessary for semantics, while cherry pick #2 is needed for a clean
> context only, and has no impact for this test.)
>
> That is, in total, I added the following four patches to the Fedora 24
> package:
>
> 1 xfree86: recognize primary BUS_PCI device in xf86IsPrimaryPlatform()
> 2 config: fix GPUDevice fail when AutoAddGPU off + BusID
> 3 xfree86: Make adding unclaimed devices as GPU devices a separate step
> 4 xfree86: Try harder to find atleast 1 non GPU Screen
>
> You can find the scratch build that I used for testing here:
>
>   xorg-x11-server-1.18.4-4.hans_bz1366842_2.fc24
>   http://koji.fedoraproject.org/koji/taskinfo?taskID=15875087
>
> Another reason I used F24's X server as basis, rather than upstream
> HEAD, is that Fedora 24 is pretty young, and it's already on kernel
> 4.7.4, and I believe it will soon move to kernel 4.8, without
> (necessarily) rebasing its X server package to upstream. IOW the kernel
> upgrade to 4.8 will break X in Fedora 24 too, and then I expect the
> Fedora X maintainers would have to cherry pick those two patches as
> dependencies just the same.
>
> To summarize, the patches don't seem to help. I shall nonetheless thank
> you for spending your Friday on this!

Hmm, do you have a xorg.conf file lying around somewhere, the message
about the xserver not being able to find an entry for screen 0 does
not make sense ...

Anyways, Monday is another day we can look at this ...

Regards,

Hans