1711266 - Compositor crash on KDE Wayland by setting gfx.webrender.compositor.force-enabled=true

Status: RESOLVED MOVED

(Core :: Widget: Gtk, defect, P3)

Description

[Henrique Sant'Anna]

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:90.0) Gecko/20100101 Firefox/90.0

Steps to reproduce:

I updated firefox-nightly on Arch Linux to 90.0a1 (2021-05-13) and I'm getting compositor crash on KDE Plasma Wayland (kwin_wayland) every time firefox-nightly is started.

Tested with firefox-nightly --safe-mode and that way kwin_wayland compositor will not crash.

So I figured out that it was related to gfx.webrender.compositor.force-enabled=true about:config setting.

Opening firefox-nightly on XWayland (works) and setting gfx.webrender.compositor.force-enabled=false solved the compositor crashing, so I can start the current nightly version as an Wayland client again.

Actual results:

firefox-nightly 90.0a1 (2021-05-13) will crash the kwin_wayland compositor when firefox-nightly is started.

The previous version, firefox-nightly 90.0a1 (2021-05-07), was working good with gfx.webrender.compositor.force-enabled=true.

Expected results:

firefox-nightly should not crash wayland compositor when firefox-nightly starts.

Comment 1

[BugBot [:suhaib / :marco]]

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

Comment 2

[Martin Stránský [:stransky] (ni? me)]

You may want to file this one at https://bugs.kde.org/ which is KDE bug tracker.

Comment 3

[Robert Mader [:rmader]]

Odd, KDE AFAIK doesn't support wp_viewporter yet and should be force-deactivated in https://searchfox.org/mozilla-central/source/gfx/thebes/gfxPlatformGtk.cpp#242

Henrique, can you confirm that the output of wayland-info | grep wp_viewporter is empty? Or does it say something like the following?

interface: 'wp_viewporter',                              version:  1, name: 14

That being said: Wayland compositor crashes are always their bugs, at least mainly. I.e. won't fix here.

Comment 4

[Robert Mader [:rmader]]

P.S. until bug 1699985 gfx.webrender.compositor.* simply did nothing, so there's no point on turning them on manually. That being said, it would of course be wonderful if KWin starts supporting the features necessary, see https://bugs.kde.org/show_bug.cgi?id=434631

Comment 5

[Henrique Sant'Anna]

(In reply to Robert Mader [:rmader] from comment #3)

Henrique, can you confirm that the output of wayland-info | grep wp_viewporter is empty? Or does it say something like the following?

Here is the output:

interface: 'wp_viewporter', version: 1, name: 8

Comment 6

[Robert Mader [:rmader]]

Oh ok, thanks :) Then everything works as expected on the FF side and you are running into a bad compositor bug. Do you by chance run KWinFT? I thought the regular KWin doesn't have wp_viewporter.

Closing this bug as we don't need to track compositor bugs for settings that are not enabled by default. We'll need careful checking before enabling this feature by default any way. Please open an issue for the compositor you are using and link it here.

Comment 7

[Henrique Sant'Anna]

(In reply to Robert Mader [:rmader] from comment #4)

P.S. until bug 1699985 gfx.webrender.compositor.* simply did nothing, so there's no point on turning them on manually. That being said, it would of course be wonderful if KWin starts supporting the features necessary, see https://bugs.kde.org/show_bug.cgi?id=434631

Thanks Robert, this makes sense.

I enabled gfx.webrender.compositor.force-enabled=true months ago since when I changed from KDE Plasma X11 to Wayland, and before firefox-nightly 90.0a1 (2021-05-13) it had no effect, but since this push to Firefox the kwin_wayland compositor will crash when Firefox starts with that setting enabled.

I opened a bug to report the crash on compositor side: https://bugs.kde.org/show_bug.cgi?id=437115
But it was closed as (supposedly) fixed (which I think it is probably wrong, I'm going to test the compositor from git next days, and lets see it).

Anyway, the report that I did is probably a duplicate from your bug report asking for wp_viewporter support, that you opened there and that you already mentioned:
https://bugs.kde.org/show_bug.cgi?id=434631

Thank you for your attention and support.

Comment 8

[Robert Mader [:rmader]]

Thanks. Vlad is following FF Wayland development quite closely AFAIK so I'd assume he knows what he's talking about :) So the crash is likely fixed in newer Kwin, just not the 5.21 series yet.

Comment 9

[Vlad Zahorodnii [:zzag]]

Yes, this crash will be fixed in 5.22.0 (there won't be any 5.21.x releases anymore). As for the wp_viewport protocol, kwin has been supporting it for quite a while now. :)

Comment 10

[Henrique Sant'Anna]

(In reply to Vlad Zahorodnii [:zzag] from comment #9)

Yes, this crash will be fixed in 5.22.0 (there won't be any 5.21.x releases anymore). As for the wp_viewport protocol, kwin has been supporting it for quite a while now. :)

Thank you, Vlad!! 🤩

I tested with kwin_wayland from git master and I can confirm that it is fixed.

Compositor will not crash anymore, even with gfx.webrender.compositor.force-enabled=true on Firefox.

Comment 11

[Robert Mader [:rmader]]

Great to hear that! Keep in mind that it's still alpha quality from the FF side. But if things keep on progressing as fast as they do atm, we might be able to start rolling things out by default by the time the fall distributions come out.