[Intel-gfx] [Linux v4.0-rc5] Warnings in drm_framebuffer_reference() and drm_atomic_check_only()

[Sedat Dilek]

On Wed, Mar 25, 2015 at 3:34 PM, Takashi Iwai <tiwai at suse.de> wrote:
> At Wed, 25 Mar 2015 14:26:50 +0100,
> Daniel Vetter wrote:
>>
>> On Tue, Mar 24, 2015 at 07:09:03PM +0100, Sedat Dilek wrote:
>> > On Mon, Mar 23, 2015 at 9:25 AM, Daniel Vetter <daniel at ffwll.ch> wrote:
>> > > On Mon, Mar 23, 2015 at 07:25:27AM +0100, Sedat Dilek wrote:
>> > >> Hi,
>> > >>
>> > >> I did my weekly update of the Linux RC (here: v4.0-rc5) and fell over
>> > >> some warning in the drm area.
>> > >>
>> > >> Please have a look...
>> > >
>> >
>> > Hi Daniel,
>> >
>> > > Just to confirm: Both are new in -rc5 and haven't been around in -rc4?
>> > >
>> >
>> > Yeah, rc4 was OK but with rc5 I have seen these warnings.
>> >
>> > > Also can you pls give -nightly a spin and see what happens there?
>> > >
>> >
>> > drm-intel-nightly (2015y-03m-24d-09h-19m-43s UTC) pulled on top of rc5
>> > does not show any warnings in the drm | i915 area.
>>
>> drm-fixes has 2 cherry-picks from -next to address the worst offenders,
>> there's one more which is waiting for confirmation:
>>
>> commit fb9981aa675eb7b398849915364916fd98833cfa
>> Author: Damien Lespiau <damien.lespiau at intel.com>
>> Date:   Thu Feb 5 19:24:25 2015 +0000
>>
>>     drm/i915: Fix atomic state when reusing the firmware fb
>>
>> Please apply that commit from -next on top of drm-fixes and retest.
>
> The problem is introduced by the commit
> 319c1d420a0b62d9dbb88104afebaabc968cdbfa
>     drm/i915: Ensure plane->state->fb stays in sync with plane->fb
>
> Obviously it accesses the uninitialized kref in
> get_initial_plane_config().
>
> The commit in next
> f55548b5af87ebfc586ca75748947f1c1b1a4a52
>     drm/i915: Don't try to reference the fb in get_initial_plane_config()
>
> fixes the bug itself, but it leads to another similar warnings.  For
> avoiding this, yet another cherry-picks (including the commit you
> mentioned above):
>
> fb9981aa675eb7b398849915364916fd98833cfa
>     drm/i915: Fix atomic state when reusing the firmware fb
> 2d14030b1a9d0e89cfdca6f16851e2eac8cb4de0
>     drm/i915: Store the initial framebuffer in initial_plane_config
>
> then warnings are finally gone.
>
> But, the second one can't be applied cleanly, so I had to adjust many
> codes manually by replacing primary fb references.
>
>
> Takashi

Hi Takashi, hi Daniel,

first of all thank you for your replies.
The last days I did not use my notebook and will try
"drm-intel-fixes-2015-03-26".
Takashi, is that Git branch on top of rc5 OK for you?

Regards,
- Sedat -