1705208 - Unable to start Firefox (webrender fails and we don't fallback to anything), on a system where my graphics are temporarily horked and e.g. glxgears won't start

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect, P3)

Description

[Daniel Holbert [:dholbert]]

STR:

1. Get your system into a state where glxgears won't start. [hand-wave]
   I'm not sure how I did this, but this is the state that my Dell laptop (running Ubuntu) is currently in. It may've been a system update that I installed earlier today.

2. Start Firefox, with gfx.webrender.enabled (e.g. mozregression -- launch [date] --setpref "gfx.webrender.enabled:true")

ACTUAL RESULTS:
No Firefox window appears.

EXPECTED RESULTS:
Firefox should start (in some sort of fallback rendering mode, if possible)

mozregression tells me this started with bug 1701236

Comment 1

[Andrew Osmond [:aosmond] (he/him)]

A user can get stuck trying to use full WebRender accidently when:

1. They force WR on via a pref.
2. GfxInfo failed for some reason (e.g. glxtest failed) which denies them permission to use SW-WR.
3. They are in nightly or early beta, in which case fallback to SW-WR is on, and fallback to Basic is off due to default pref settings.
4. They fail to initialize WR.
5. They try to fallback, but SW-WR is disabled, and they cannot fallback to Basic, and thus it retries with WR.

Comment 2

[Andrew Osmond [:aosmond] (he/him)]

Attachment: Bug 1705208 - Force allow fallback to Software WebRender if fallback to Basic is disabled.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/ddeb97eb8555
Force allow fallback to Software WebRender if fallback to Basic is disabled. r=gfx-reviewers,sotaro

Comment 4

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/ddeb97eb8555