GNOME Bugzilla – Bug 742911
Windows unredirection causes crashes with UXA
Last modified: 2015-02-02 14:39:47 UTC
1) Download the MX Simulator demo http://mxsimulator.com/mxsimulator-demo-1_8-linux-x86.tar.gz 2) Decompress it and launch it with ./mx 3) Wait a bit for the window to get unredirected 4) The game will crash along with gnome-shell. This issue doesn't appear when SNA is enabled. I'm also observing a white flash when unredirection kicks in with UXA. Using mutter as standalone doesn't exhibit the issue. I could observe the crash when watching a video with Popcorn Time too. gnome-shell 3.14.3 xf86-video-intel 2.99.917 xorg-server 1.16.3 linux 3.17.6 Intel HD 3000
Both MX Simulator and gnome-shell are printing after the crash: >Failed to open BO for returned DRI2 buffer (1366x768, dri2 back buffer, named 2). >This is likely a bug in the X Server that will lead to a crash soon. >Segmentation fault (core dumped)
Created attachment 294516 [details] Screenshot just after MX/gnome-shell crashes
This is apparently a driver bug.
commit 6db906ea8188cd7f731e5ef7391115ee8f5c17c8 Author: Chris Wilson <chris@chris-wilson.co.uk> Date: Fri Jan 30 16:49:06 2015 +0000 uxa/dri2: Reimplement triple buffer support Since xorg-server-1.12.0, Xorg has supported adjusting the client swap limits allowing us the implemention of triple buffered flipping with accurate event timestamps. Given that the current implemention has an issue tracking the right GEM name across composite unredirection, it is an approximate juncture to tackle both bugs. Bugzilla: https://bugzilla.gnome.org/show_bug.cgi?id=742911#c1 Testcase: dri2-race + gnome-shell Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Fwiw, the unredirection flash appears not to have been a figment of Clément's imagination: https://bugzilla.gnome.org/show_bug.cgi?id=743858