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

[Takashi Iwai]

At Fri, 27 Mar 2015 12:01:33 +0100,
Sedat Dilek wrote:
> 
> 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?

The fixes have been already merged to Linus tree.


Takashi