Bug 1133166

I have got the same screen flickering issue with the same iso image. i have tested it in a virtual machine (libvirt) having f20 gnome as a base os with 1 cpu, 1024 ram and 20 gb disk space for installation.

Created attachment 929857 [details]
Screen flickering

The flickering started for me on clicking on a dropdown box; before that, the screen was stable.

In my case, the dropdown box I selected was in the Date and Time screen and clicked on the region/city dropdowns.

Hello,

The flickering was quite random but a lot in my case. It was almost difficult to keep looking at the screen. Complete machine install on two machines. 

anaconda-21.48.2-1.fc21.x86_64


Video: https://db.tt/Zc5amiN3

Thanks,
Warm regards,
Ankur

Also seen in workstation live TC3 and KDE live TC3 installs to bare metal
see BZ 1103496 comments 30

I see this with nightly Fedora-Live-Workstation-x86_64-21-20140824.iso. I'm going to propose this as an Alpha blocker, even though we obviously have no criterion for this. Everything technically works, but it's so uncomfortable (at least for me, I guess not just me), that it makes operating anaconda really difficult.

Yeah, I've seen this in live installs too. Not sure I'd call it a blocker as it's not so terrible to work around, but it is kinda annoying and does look bad.

Some additional information:
Blinking starts on 42% of installation for me, regardless whether I entered the rootpw/user creation dialog. It switches between the wallpaper and anaconda. If you go to overview mode in Gnome, it does not blink. If you return back, it blinks again.

The image link is here:
https://kojipkgs.fedoraproject.org//work/tasks/4637/7444637/Fedora-Live-Workstation-x86_64-21-20140824.iso

For older images, I think I might have seen the blinking even in the main hub, not just during installation, but I'm not really sure. But the above reports seem to confirm it.

As far as I can tell this only happens in gnome-shell, and it seems to be related to anaconda running in fullscreen (i.e., gtk_window_fullscreen) mode. The gnome-shell process takes up as much CPU as it can get when all of this flickering business starts. Reassigning. Help us, gnome-shell, you're our only hope.

A few more details from #fedora-desktop conversation with drago01:

<drago01> kparal: ok can you do "alt-f2" "lg" enter "Meta.disable_unredirect_for_screen(global.screen);" and then try anaconda
<kparal> drago01: if I disable unredirect, it stops flickering. if I enable it again, it starts flickering again. happens immediately

<drago01> kparal: ok, one more thing can you try to get a backtrace while the flicker is ongoing?
<kparal> drago01: http://paste.fedoraproject.org/128639/
<kparal> drago01: and a second attempt here, in case it's different: http://paste.fedoraproject.org/128642/
<drago01> kparal: hmm ok both aren't telling much just "drawing stuff"

<kparal> drago01: another interesting thing is this: anaconda flickering -> run terminal -> switch back and forth between anaconda and terminal -> close terminal -> you see desktop (because anaconda window got minimized automatically) -> switch back to anaconda -> it no longer flickers
<drago01> kparal: as for your observation that means that anaconda does not get unredirected anymore ... actually it shouldn't but apperently it does 100 full window damages in a row and thus gets detected as a "game"

<mclasen> I've seen similar flicker with who-t's user study app
<mclasen> drago01: can you see this ? http://libinput-whot.rhcloud.com/
<mclasen> or go straight here, I guess: http://copr.fedoraproject.org/coprs/whot/libinput-userstudy/
<drago01> mclasen: ah nice reproduces
<drago01> mclasen: and the window isn't sized corrected

<drago01> kparal: can you confirm that it does *not* happen when you run just mutter (no gnome-shell) i.e "mutter --replace " in a terminal
<kparal> drago01: so, do you want the short or the complicated answer?
<drago01> kparal: both ;)
<kparal> the screen is not flickering at all during installation
<kparal> however, I noticed that if I hover my mouse over some of the "user settings" icon to let a popup text appear and then move it around to let the popup text disappear, the screen flashes briefly, once or twice
<kparal> again, I see the background, lime color this time
<kparal> this flashing right after popup disappears does not happen in the beginning of the installation, but it does happen at the end of the installation
<kparal> which matches screen flickering issues under gnome-shell - that also happens only in the second half of the installation
<kparal> not sure whether it is related or not
<drago01> kparal: ok

Can someone please test with this scratch build (once its done): http://koji.fedoraproject.org/koji/taskinfo?taskID=7453921 

I didn't test with anaconda but could reproduce the bug with libinput-userstudy; the bug looks very similar so that fix should work for anaconda too.

OK I have built a proper package http://koji.fedoraproject.org/koji/taskinfo?taskID=7454039 with the upstream version of the patch (it does the same).

I think it worked. I updated mutter on Fedora-Live-Workstation-x86_64-21-20140824.iso with the package from comment 12 and restarted gdm, and the install looks fine now. Thanks!

(In reply to David Shea from comment #13)
> I think it worked. I updated mutter on
> Fedora-Live-Workstation-x86_64-21-20140824.iso with the package from comment
> 12 and restarted gdm, and the install looks fine now. Thanks!

OK, thanks for testing. I guess we can close this one now?

Package is tagged for F21, so for now yeah, we'll re-open if it turns out not to be fixed.

*** Bug 1134564 has been marked as a duplicate of this bug. ***

Yesterday nightly contains the new mutter and anaconda no longer flickers. Thanks, drago01!

*** Bug 1134683 has been marked as a duplicate of this bug. ***