1296733 - Investigate potential Mesa races with GL layers and WebGL tests

Status: RESOLVED WONTFIX

(Core :: Graphics, defect)

Description

[Andrew Comminos [:acomminos]]

There are a few new intermittents for non-e10s WebGL mochitests after bug 594876 enabled GL layers by default on TaskCluster instances. As these issues only seem to surface in non-e10s tests, I suspect that we're running into some raciness in LLVMPipe with the compositor and content both using a GL context.

Here are some ones I've seen so far;

> TEST-UNEXPECTED-FAIL | dom/canvas/test/webgl-conf/generated/test_conformance__textures__video__tex-2d-rgba-rgba-unsigned_byte.html | application terminated with exit code 11

> TEST-UNEXPECTED-FAIL | dom/canvas/test/webgl-conf/generated/test_conformance__textures__video__tex-2d-rgb-rgb-unsigned_byte.html | application terminated with exit code 11

> TEST-UNEXPECTED-FAIL | dom/canvas/test/webgl-conf/generated/test_conformance__ogles__GL__functions__functions_025_to_032.html | application terminated with exit code 11 

> SUMMARY: AddressSanitizer: 288 byte(s) leaked in 4 allocation(s).

The good news is that we won't permit acceleration with LLVMPipe in nightlies, only on the test infrastructure. It might be worth disabling layers acceleration for WebGL mochitests on non-e10s builds for now.

Comment 1

[Andrew Comminos [:acomminos]]

It appears that LLVMPipe is known to lack thread safety, at least with the version we're using. There's a commit included in Mesa 10.4 that claims to fix it up;

https://lists.freedesktop.org/archives/mesa-dev/2014-July/063248.html

Let's turn off these tests for now, and investigate an upgrade path to Mesa 10.4.

Comment 2

[Andrew Comminos [:acomminos]]

Attachment: Bug 1296733 - Disable layers acceleration for WebGL mochitests on Linux.

Review commit: https://reviewboard.mozilla.org/r/73012/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/73012/

Comment 3

[Andrew Comminos [:acomminos]]

Comment on attachment 8783040 [details]
Bug 1296733 - Disable layers acceleration for WebGL mochitests on Linux.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/73012/diff/1-2/

Comment 4

[Jeff Muizelaar [:jrmuizel]]

Comment on attachment 8783040 [details]
Bug 1296733 - Disable layers acceleration for WebGL mochitests on Linux.

https://reviewboard.mozilla.org/r/73012/#review70802

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b394fa844080
Disable layers acceleration for WebGL mochitests on Linux. r=jrmuizel

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/b394fa844080

Comment 7

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

The leave-open keyword is there and there is no activity for 6 months.
:davidb, maybe it's time to close this bug?