1755607 - Hardware video decoding does not work in Firefox 98 beta on Linux

Status: RESOLVED DUPLICATE of bug 1751363

(Core :: Audio/Video: Playback, defect)

Description

[Michael Marley]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:98.0) Gecko/20100101 Firefox/98.0

Steps to reproduce:

-Upgraded from Firefox 97 to Firefox 98 beta
-Previously had media.ffmpeg.vaapi.enabled=true set in about:config
-Played a YouTube video

Actual results:

-intel_gpu_top reported only a very short burst of "Video" activity when the video first started playing followed by 0%
-4k60 YouTube videos, which previously played smoothly with minimal CPU usage now play jerkily with very high CPU usage

Expected results:

-intel_gpu_top should have reported continuous "Video" activity
-4k60 videos should continue to play smoothly

This happened after upgrading from Firefox 97 where the video decoding worked fine when the above option was set. I have tested it on two systems, both with Intel graphics. One is Broadwell and the other is Coffeelake. Both systems have enhanced-h264ify installed and set to block codecs that each system cannot hardware accelerate.

Simultaneously with video playback starting, I do see:
libva info: VA-API version 1.13.0
libva info: User environment variable requested driver 'i965'
libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/i965_drv_video.so
libva info: Found init function __vaDriverInit_1_10
libva info: va_openDriver() returns 0
on the console output and no error messages are displayed.

Comment 1

[Michael Marley]

Further testing reveals that starting firefox with MOZ_DISABLE_RDD_SANDBOX=1 results in properly-working hardware video decoding, so it seems like something with the sandbox is busted.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Audio/Video: Playback' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 3

[asterix52]

Attachment: with sandbox.txt

Comment 4

[asterix52]

Attachment: without sandbox.txt

Comment 5

[asterix52]

I have also problem with video playback in sandbox mode.firefox 98 b6

Comment 6

[Raluca Popovici, Desktop QA]

Attachment: 3CCBFFAD-CEB1-408E-B055-BFCEA03DEE83.jpg

Comment 7

[Raluca Popovici, Desktop QA]

Attachment: 4AB8CD6F-8B97-4062-AF1C-5A27C7AE242D.jpg

Comment 8

[Raluca Popovici, Desktop QA]

Hello,
I installed Fx 97.0b8 on my machine Ubuntu 21.04, and had media.ffmpeg.vaapi.enabled=true set in about:config. Upgraded to Fx 98.0b7 and start a 4k YouTube video.
After a while for the RDD Process the CPU increased to ~35 and if I let the 4k video playing for ~1 hour the Firefox was not responding and the CPU increased to ~51. Please see the attached screenshots

Comment 9

[Darkspirit]

(In reply to Michael Marley from comment #1)

Further testing reveals that starting firefox with MOZ_DISABLE_RDD_SANDBOX=1 results in properly-working hardware video decoding, so it seems like something with the sandbox is busted.

Yes.