[Intel-gfx] [PATCH 53/59] drm/arc: Move to drm/tiny

Fri Jul 17 09:04:07 UTC 2020

On Tue, Jun 09, 2020 at 03:02:14PM +0200, Daniel Vetter wrote:
> Hi Eugeniy,
> 
> Very much appreciated, and kinda expected. That 2nd backtrace really
> confuses me, so "something strange is going on" and the bisect looks
> funny is within expectations. Hopefully we can track down what's going
> on.

I'm going to resend the entire pile with the bugfix below and all rebased,
I think retesting it all is probably a good idea now, since quite some
time passed.

Cheers, Daniel

> 
> Thanks, Daniel
> 
> On Tue, Jun 9, 2020 at 2:08 PM Eugeniy Paltsev
> <Eugeniy.Paltsev at synopsys.com> wrote:
> >
> > Hi Daniel,
> >
> > I've got pretty strange results so I need some time to investigate it and probably retest.
> > I'll send you update in a few days.
> >
> > ---
> >  Eugeniy Paltsev
> >
> >
> > ________________________________________
> > From: Daniel Vetter <daniel at ffwll.ch>
> > Sent: Friday, June 5, 2020 22:55
> > To: Eugeniy Paltsev
> > Cc: Intel Graphics Development; DRI Development; Daniel Vetter; Sam Ravnborg; Alexey Brodkin; snps-arc at lists.infradead.org
> > Subject: Re: [PATCH 53/59] drm/arc: Move to drm/tiny
> >
> > Hi Eugeniy,
> >
> > Thanks for testing. I looked at the second one (I hoped it would just
> > magically disappear) and I still don't understand what's going on
> > there. My patch series isn't touching that area at all, so really
> > confused.
> >
> > I squashed in the bugfix from the previous round into the right
> > patches, and pushed a branch with just the arcpgu changes here:
> > https://urldefense.com/v3/__https://cgit.freedesktop.org/*danvet/drm/log/?h=for-eugeniy__;fg!!A4F2R9G_pg!IJ1o4XiXVdStPu--Q-SCTUpRbsbqrjX255R34nuD7L7ptPywOy4SKr21dwSpfOkXIVqH5pM$
> >
> > Maybe it's something in my pile of not-so-tested stuff :-)
> >
> > Can you pls test this? And if it still fails, try to bisect where it breaks?
> >
> > Thanks, Daniel
> >
> > On Thu, Jun 4, 2020 at 9:00 PM Eugeniy Paltsev
> > <Eugeniy.Paltsev at synopsys.com> wrote:
> > >
> > > I've tested your change and one issue gone.
> > >
> > > However I still see kernel crash (due to invalid read in kernel mode by 0x0 address) on weston stop:
> > > ----------------------------------->8-------------------------------------------
> > > Oops
> > > Path: (null)
> > > CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.7.0-rc6-01594-g4ceda91a4176-dirty #6
> > > Workqueue: events drm_mode_rmfb_work_fn
> > > Invalid Read @ 0x00000000 by insn @ drm_gem_fb_destroy+0x32/0x130
> > > ECR: 0x00050100 EFA: 0x00000000 ERET: 0x813b9a76
> > > STAT32: 0x80080602 [IE K     ]  BTA: 0x813b9a72
> > > BLK: drm_gem_fb_destroy+0xc0/0x130
> > >  SP: 0x9f055ea4  FP: 0x00000000
> > > LPS: 0x813560ec LPE: 0x813560f0 LPC: 0x00000000
> > > r00: 0x00000000 r01: 0x9f6a6100 r02: 0x00000001
> > > r03: 0x9fd5dde8 r04: 0x810f5de8 r05: 0x00000000
> > > r06: 0x00000000 r07: 0x00000000 r08: 0x000000e1
> > > r09: 0x00000000 r10: 0x00000000 r11: 0x000000e1
> > > r12: 0x813b9b04
> > >
> > > Stack Trace:
> > >   drm_gem_fb_destroy+0x32/0x130
> > >   drm_framebuffer_remove+0x1d2/0x358
> > >   drm_mode_rmfb_work_fn+0x28/0x38
> > >   process_one_work+0x19a/0x358
> > >   worker_thread+0x2c4/0x494
> > >   kthread+0xec/0x100
> > >   ret_from_fork+0x18/0x1c
> > > ----------------------------------->8-------------------------------------------
> > >
> > >
> > > The stack traces may vary but always end in drm_gem_fb_destroy:
> > > ----------------------------------->8-------------------------------------------
> > > Stack Trace:
> > >   drm_gem_fb_destroy+0x32/0x130
> > >   drm_mode_rmfb+0x10e/0x148
> > >   drm_ioctl_kernel+0x70/0xa0
> > >   drm_ioctl+0x284/0x410
> > >   ksys_ioctl+0xea/0xa3c
> > >   EV_Trap+0xcc/0xd0
> > > ----------------------------------->8-------------------------------------------
> > > Stack Trace:
> > >   drm_gem_fb_destroy+0x32/0x130
> > >   drm_fb_release+0x66/0xb0
> > >   drm_file_free.part.11+0x112/0x1bc
> > >   drm_release+0x80/0x120
> > >   __fput+0x98/0x1bc
> > >   task_work_run+0x6e/0xa8
> > >   do_exit+0x2b4/0x7fc
> > >   do_group_exit+0x2a/0x8c
> > >   get_signal+0x9a/0x5f0
> > >   do_signal+0x86/0x23c
> > >   resume_user_mode_begin+0x88/0xd0
> > > ----------------------------------->8-------------------------------------------
> > >
> > >
> > > ---
> > >  Eugeniy Paltsev
> > >
> > >
> > > ________________________________________
> > > From: Daniel Vetter <daniel at ffwll.ch>
> > > Sent: Thursday, June 4, 2020 14:19
> > > To: Eugeniy Paltsev
> > > Cc: Intel Graphics Development; DRI Development; Daniel Vetter; Sam Ravnborg; Alexey Brodkin
> > > Subject: Re: [PATCH 53/59] drm/arc: Move to drm/tiny
> > >
> > > Hi Eugeniy,
> > >
> > > Apologies, somehow I missed your mail. I looked at the code again, and I
> > > think I fumbled something. Does the below diff help to prevent the issues?
> > >
> > > Thanks, Daniel
> > >
> > >
> > > diff --git a/drivers/gpu/drm/tiny/arcpgu.c b/drivers/gpu/drm/tiny/arcpgu.c
> > > index 857812f25bec..33d812a5ad7f 100644
> > > --- a/drivers/gpu/drm/tiny/arcpgu.c
> > > +++ b/drivers/gpu/drm/tiny/arcpgu.c
> > > @@ -228,6 +228,9 @@ static void arc_pgu_update(struct drm_simple_display_pipe *pipe,
> > >         struct arcpgu_drm_private *arcpgu;
> > >         struct drm_gem_cma_object *gem;
> > >
> > > +       if (!pipe->plane.state->fb)
> > > +               return;
> > > +
> > >         arcpgu = pipe_to_arcpgu_priv(pipe);
> > >         gem = drm_fb_cma_get_gem_obj(pipe->plane.state->fb, 0);
> > >         arc_pgu_write(arcpgu, ARCPGU_REG_BUF0_ADDR, gem->paddr);
> > > --
> > > Daniel Vetter
> > > Software Engineer, Intel Corporation
> > > +41 (0) 79 365 57 48 - https://urldefense.com/v3/__http://blog.ffwll.ch__;!!A4F2R9G_pg!P0EvyJfMuDwqbeZmHZM5S9po30QWr4KgGrggRirNfgo7wrRXfnUO-8iq0AA4fQCW2WGPlDc$
> >
> >
> >
> > --
> > Daniel Vetter
> > Software Engineer, Intel Corporation
> > +41 (0) 79 365 57 48 - https://urldefense.com/v3/__http://blog.ffwll.ch__;!!A4F2R9G_pg!IJ1o4XiXVdStPu--Q-SCTUpRbsbqrjX255R34nuD7L7ptPywOy4SKr21dwSpfOkXpn86Q20$
> 
> 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch