** Description changed: - Maverick Xorg gesture handling writes events to clients in signal - context. This causes corruption and eventual X server crash. + Justification: + ============= + Regression from Ubuntu 10.04, causing an Xserver crash after performing a gesture. The X crash risks losing user data from unsaved documents in applications. + Fix: + === + The cause is a call to WriteToClient in signal context during input event processing. The call was added for gesture event handling, but it appears that something in WriteToClient is unsafe in signal context. Patches have been added to xserver-xorg-input-evdev and xorg-server to queue gesture events in the X server and propagate them to clients in normal context. + + Test case: + ========= + Perform multitouch gestures in a gesture-enabled environment. The Unity window manager should suffice. However, this bug is indeterministic. Some users may never see the bug, others may see it multiple times per day. + + Regression Potential: ==================== + Moderate due to the changes to two interrelated packages and the size of the patches. A depends has been added to xserver-xorg-input-evdev to ensure it is installed with the correlated xorg-server packages. An X crash at the beginning of a gesture would occur if the packages are installed improperly. However, A newer X server with an old evdev input module would not pose any regression potential due to interdependencies. + + The size of the patches may cause some concern, but they are the minimal + amount required to address the bug in a maintainable manner. + + Original Report: + =============== Binary package hint: xorg I have X crashes a couple of times a day. Could not reproduce it deterministically. ProblemType: Bug DistroRelease: Ubuntu 10.10 Package: xorg 1:7.5+6ubuntu3 ProcVersionSignature: Ubuntu 2.6.35-23.36-generic-pae 2.6.35.7 Uname: Linux 2.6.35-23-generic-pae i686 NonfreeKernelModules: nvidia wl .proc.driver.nvidia.version: NVRM version: NVIDIA UNIX x86 Kernel Module 260.19.06 Mon Sep 13 06:35:06 PDT 2010 GCC version: gcc version 4.4.5 (Ubuntu/Linaro 4.4.4-14ubuntu5) Architecture: i386 Date: Tue Nov 2 14:25:08 2010 InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release i386 (20100816.1) MachineType: Apple Inc. MacBook5,1 ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-23-generic-pae root=UUID=14caef4c-d30c-4e34-8e4f-94a6ce5fc47e ro quiet splash ProcEnviron: LANGUAGE=en LANG=en_US.utf8 SHELL=/bin/bash SourcePackage: xorg dmi.bios.date: 04/27/09 dmi.bios.vendor: Apple Inc. dmi.bios.version: MB51.88Z.007D.B03.0904271443 dmi.board.asset.tag: Base Board Asset Tag# dmi.board.name: Mac-F42D89A9 dmi.board.vendor: Apple Inc. dmi.board.version: Proto dmi.chassis.asset.tag: Asset Tag# dmi.chassis.type: 10 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-F42D89A9 dmi.modalias: dmi:bvnAppleInc.:bvrMB51.88Z.007D.B03.0904271443:bd04/27/09:svnAppleInc.:pnMacBook5,1:pvr1.0:rvnAppleInc.:rnMac-F42D89A9:rvrProto:cvnAppleInc.:ct10:cvrMac-F42D89A9: dmi.product.name: MacBook5,1 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. system: distro: Ubuntu codename: maverick architecture: i686 kernel: 2.6.35-23-generic-pae
** Description changed: Justification: ============= Regression from Ubuntu 10.04, causing an Xserver crash after performing a gesture. The X crash risks losing user data from unsaved documents in applications. Fix: === The cause is a call to WriteToClient in signal context during input event processing. The call was added for gesture event handling, but it appears that something in WriteToClient is unsafe in signal context. Patches have been added to xserver-xorg-input-evdev and xorg-server to queue gesture events in the X server and propagate them to clients in normal context. + + Note that the fix is not proposed for Natty because the gesture stack + will be removed from Natty and moved to the X client side. The Natty + gesture code will likely be removed in the next few weeks during the + transition to X server 1.10. Test case: ========= Perform multitouch gestures in a gesture-enabled environment. The Unity window manager should suffice. However, this bug is indeterministic. Some users may never see the bug, others may see it multiple times per day. Regression Potential: ==================== Moderate due to the changes to two interrelated packages and the size of the patches. A depends has been added to xserver-xorg-input-evdev to ensure it is installed with the correlated xorg-server packages. An X crash at the beginning of a gesture would occur if the packages are installed improperly. However, A newer X server with an old evdev input module would not pose any regression potential due to interdependencies. The size of the patches may cause some concern, but they are the minimal amount required to address the bug in a maintainable manner. Original Report: =============== Binary package hint: xorg I have X crashes a couple of times a day. Could not reproduce it deterministically. ProblemType: Bug DistroRelease: Ubuntu 10.10 Package: xorg 1:7.5+6ubuntu3 ProcVersionSignature: Ubuntu 2.6.35-23.36-generic-pae 2.6.35.7 Uname: Linux 2.6.35-23-generic-pae i686 NonfreeKernelModules: nvidia wl .proc.driver.nvidia.version: NVRM version: NVIDIA UNIX x86 Kernel Module 260.19.06 Mon Sep 13 06:35:06 PDT 2010 GCC version: gcc version 4.4.5 (Ubuntu/Linaro 4.4.4-14ubuntu5) Architecture: i386 Date: Tue Nov 2 14:25:08 2010 InstallationMedia: Ubuntu 10.04.1 LTS "Lucid Lynx" - Release i386 (20100816.1) MachineType: Apple Inc. MacBook5,1 ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-23-generic-pae root=UUID=14caef4c-d30c-4e34-8e4f-94a6ce5fc47e ro quiet splash ProcEnviron: LANGUAGE=en LANG=en_US.utf8 SHELL=/bin/bash SourcePackage: xorg dmi.bios.date: 04/27/09 dmi.bios.vendor: Apple Inc. dmi.bios.version: MB51.88Z.007D.B03.0904271443 dmi.board.asset.tag: Base Board Asset Tag# dmi.board.name: Mac-F42D89A9 dmi.board.vendor: Apple Inc. dmi.board.version: Proto dmi.chassis.asset.tag: Asset Tag# dmi.chassis.type: 10 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-F42D89A9 dmi.modalias: dmi:bvnAppleInc.:bvrMB51.88Z.007D.B03.0904271443:bd04/27/09:svnAppleInc.:pnMacBook5,1:pvr1.0:rvnAppleInc.:rnMac-F42D89A9:rvrProto:cvnAppleInc.:ct10:cvrMac-F42D89A9: dmi.product.name: MacBook5,1 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. system: distro: Ubuntu codename: maverick architecture: i686 kernel: 2.6.35-23-generic-pae -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/670016 Title: Xorg crashes when performing gesture -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
