Opened 2 years ago

Closed 2 years ago

Last modified 18 months ago

#13091 closed Bug Report - General (fixed)

vaapi / vdpau crash in display profile code

Reported by: Stuart Auchterlonie Owned by: Peter Bennett
Priority: major Milestone: 29.1
Component: MythTV - Video Playback Version: v29-fixes
Severity: medium Keywords:
Cc: Ticket locked: no

Description

My system uses only the Intel graphics from the cpu and therefore uses VAAPI for acceleration.

I hit a situation where the frontend coredumped.

It looks like it's failed to create the vaapi context (happens occasionaly), and we noticed this and coped.

The problem then starts when the new display profile code then goes an selects a vdpau profile, which is wrong for this system. The frontend then tried to load the vdpau libraries and failed and segfaulted.

I'll attach some logs

Attachments (2)

frontend-vaapi-fail-vdpau-fail-crash.log.1 (17.5 KB) - added by Stuart Auchterlonie 2 years ago.
gdb backtrace
frontend-vaapi-fail-vdpau-fail-crash-with-verbose.log (19.5 KB) - added by Stuart Auchterlonie 2 years ago.

Download all attachments as: .zip

Change History (6)

Changed 2 years ago by Stuart Auchterlonie

gdb backtrace

Changed 2 years ago by Stuart Auchterlonie

comment:1 Changed 2 years ago by Stuart Auchterlonie

You can see starting at https://code.mythtv.org/trac/attachment/ticket/13091/frontend-vaapi-fail-vdpau-fail-crash-with-verbose.log#L223 that it is clearly deciding (correctly) that vaapi is the way to go (lines 223-225) and then it randomly chooses to try vdpau and fails (lines 226-227)

223	2017-08-04 16:28:38.341663 I  VDP: Accepting: cmp(> 0 0) w() h() framerate() codecs() dec(vaapi) cpus(2) skiploop(enabled) rend(openglvaapi) osd(opengl2) osdfade(enabled) deint(vaapionefield,vaapionefield) filt()
224	2017-08-04 16:28:38.341699 I  VDP: LoadBestPreferences(1920x1080, 25.000, h264)
225	2017-08-04 16:28:38.341758 I  VDP: LoadBestPreferences Result cmp0:> 0 0, cmp1:, prio:1, w:, h:, fps:, codecs:, decoder:vaapi, renderer:openglvaapi, deint:vaapionefield
226	2017-08-04 16:28:38.341797 I  VideoOutput: Trying video renderer: 'vdpau'
227	Failed to open VDPAU backend libvdpau_nvidia.so: cannot open shared object file: 
 No such file or directory

The other log file frontend-vaapi-fail-vdpau-fail-crash.log.1​ captures the crash, but without the --verbose playback. The two taken together should allow us to piece together what is going wrong.

Looking at https://code.mythtv.org/trac/attachment/ticket/13091/frontend-vaapi-fail-vdpau-fail-crash.log.1#L74 the stack trace goes via videodisplayprofile.cpp:585 which is right around the area of the new code.

Regards Stuart

Last edited 2 years ago by Stuart Auchterlonie (previous) (diff)

comment:2 Changed 2 years ago by Peter Bennett <pbennett@…>

Resolution: fixed
Status: newclosed

In 48111f8d6707c5a53cbb66c796046bb87c38192a/mythtv:

Fixes #13091 - Seg fault in video playback when using an alternate video output method

Fix premature deletion of VideoDisplayProfile? object.

comment:3 Changed 2 years ago by Peter Bennett <pbennett@…>

In 433f5d17312e6ffce428de959d87ae4b60a2aebf/mythtv:

Fixes #13091 - Seg fault in video playback when using an alternate video output method

Fix premature deletion of VideoDisplayProfile? object.

(cherry picked from commit 48111f8d6707c5a53cbb66c796046bb87c38192a)

comment:4 Changed 18 months ago by Peter Bennett

Owner: changed from Peter Bennett to Peter Bennett
Note: See TracTickets for help on using tickets.