** Description changed: [Impact] Users running the nouveau X driver with the egl_dri2 mesa driver may experience a windowing system crash (kwin_gles, etc.) in the nv50_screen_fence_update() routine. [Development Fix] The problem was fixed upstream in mesa 8.0 which we are shipping in Precise. The patch switches from using a context object for flushing purposes, to a screen object; the context object can go NULL sometimes which leads to the crash. [Stable Fix] Upstream also created a backport of the mesa 8.0 patch to 7.11, although at time of writing this was not yet released in a 7.11.x point release. The patch applies cleanly to the oneiric mesa and is what we're using for this SRU. [Text Case] 1. install nouveau video driver 2. call /usr/bin/es2_info from mesa-utils-extra Broken Behavior: application crashes Fixed Behavior: egl information is printed out [Regression Potential] - The scope of this patch is limited to nouveau (and specifically to newer NVIDIA cards). Indeed it probably has no effect on non-egl window systems (like Unity/Compiz), so the scope is probably quite small. + The scope of this patch is limited to nouveau (and specifically to newer NVIDIA cards of the 8xxx series and up). Indeed it probably has no effect on non-egl window systems (like Unity/Compiz), so the scope is probably quite small. Since the patch is included upstream as part of the mesa 8.0 tree, and is selected for the 7.11 stable series, the patch is likely quite safe. If there were any regressions caused by this, I would expect symptoms similar to the original bug (i.e. crashes). [Original Report] called /usr/bin/es2_info from mesa-utils-extra ProblemType: Crash DistroRelease: Ubuntu 11.10 Package: mesa-utils-extra 8.0.1+git20110129+d8f7d6b-0ubuntu2 ProcVersionSignature: Ubuntu 3.0.0-15.26-generic 3.0.13 Uname: Linux 3.0.0-15-generic x86_64 ApportVersion: 1.23-0ubuntu4 Architecture: amd64 Date: Sat Feb 4 23:52:38 2012 ExecutablePath: /usr/bin/es2_info InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012) ProcCmdline: es2_info SegvAnalysis: Segfault happened at: 0x7fcea9943fa7: mov (%rax),%eax PC (0x7fcea9943fa7) ok source "(%rax)" (0x7fceacc81000) not located in a known VMA region (needed readable region)! destination "%eax" ok SegvReason: reading unknown VMA Signal: 11 SourcePackage: mesa-demos StacktraceTop: ?? () from /usr/lib/x86_64-linux-gnu/egl/egl_gallium.so nouveau_fence_update () from /usr/lib/x86_64-linux-gnu/egl/egl_gallium.so nv50_default_flush_notify () from /usr/lib/x86_64-linux-gnu/egl/egl_gallium.so nouveau_pushbuf_flush () from /usr/lib/x86_64-linux-gnu/libdrm_nouveau.so.1 nouveau_grobj_free () from /usr/lib/x86_64-linux-gnu/libdrm_nouveau.so.1 Title: es2_info crashed with SIGSEGV in nouveau_fence_update() UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare users
-- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to mesa in Ubuntu. https://bugs.launchpad.net/bugs/926918 Title: es2_info crashed with SIGSEGV in nv50_screen_fence_update() To manage notifications about this bug go to: https://bugs.launchpad.net/mesa/+bug/926918/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
