1489354 - Firefox hangs after switching user and coming back

Status: RESOLVED DUPLICATE of bug 1492580

(Core :: Graphics, defect, P3)

Description

[V. Korn]

I can reproduce by following these steps:

1) Launch firefox
2) set layers.acceleration.force-enabled
3) restart firefox
4) Use switch user option (switch, not logout)
5) Get to system login screen, 
6) Optionally actually login\switch to other user (its usually not necessary, getting to login screen is enough)
6) Reenter system as user running firefox from 1)

expected results : Firefox works as usual
actual results : Firefox hangs completely, tabs cannot be switched, menus dont respond, if windows minimized and then restored back its completely black.

The problem can be reproduced from Nightly 63 (Build ID 20180830111745) and still present in latest Nightly.

System info Xubuntu 17.10, Nvidia 384.130 on Nvidia TI750.

Setting also layers.force-active to true makes this bug ~99% reproducible.

I'm absolutely not in position to make any assumption but problem appeared at same time as https://bugzilla.mozilla.org/show_bug.cgi?id=1484782 was fixed - got that hint from nightly-community.

Comment 1

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

You are probably right about the regressing bug. jgilbert is already investigating a very similar issue in bug 1492580.

Comment 2

[V. Korn]

I'm not really sure if it related, but starting from 64.0a1 2018-10-17 build situation got significantly worse - now Firefox tend to randomly freeze without even leaving session, just on its own. Symptoms - complete lose of response on any action. Again according to Mozillazine https://bugzilla.mozilla.org/show_bug.cgi?id=1498070 is possible culprit, since its only WebGL related bug and WebGL is one who cause hangs as it stated to https://bugzilla.mozilla.org/show_bug.cgi?id=1492580

Rolling back to 2018-10-16 build prevents random hangs.

Comment 3

[Jan]

I am hit by this too. The same issue seems to happen when you do a suspend/resume cycle, but I was also able to reproduce with switch user feature.

Bug #1484782 / https://hg.mozilla.org/integration/mozilla-inbound/rev/88973a92ac86 is definitely the culprit (did a regression test).

I also looked into Bug #1492580, but I could still reproduce the hang with the latest nightly build.

Comment 4

[Matt Brubeck (:mbrubeck)]

I could previously reproduce this bug, but since the fix for bug 1511508 landed, Firefox no longer hangs.  However, I'm now seeing a new bug which I reported as bug 1511508.

Comment 5

[Matt Brubeck (:mbrubeck)]

> since the fix for bug 1511508 landed...

Oops, I meant to write: "since the fix for bug 1492580 landed".