drm: GPF in drm_getcap

[David Herrmann]

Hi

On Sat, Nov 26, 2016 at 7:07 PM, Dmitry Vyukov <dvyukov at google.com> wrote:
> grep "card0" dmesg:
> [    5.298617] device: 'card0': device_add
> [    5.298946] PM: Adding info for No Bus:card0
> [    6.436178] device: 'card0': device_add
> [    6.436488] PM: Adding info for No Bus:card0
>
>
> # ls -l /dev/dri/card0
> crw-rw---T 1 root video 226, 0 Nov 26 18:05 /dev/dri/card0
>
> # ls -lt /sys/class/drm/card0/device/
> ls: cannot access /sys/class/drm/card0/device/: No such file or directory
>
> # ls -lt /sys/class/drm/card0/device/driver
> ls: cannot access /sys/class/drm/card0/device/driver: No such file or directory

Looks like vgem. Something like this should help:

    https://gist.github.com/dvdhrm/1bcdf4f3485aa1614a0198a7b90515e2

I wonder whether it would be more appropriate to return -ENOTSUPP rather than 0.

Thanks
David