Nice work Mikhil! Can't wait to try the patch! Thank you for your efforts. Everyone has been waiting for a resolution for quite some time. On Nov 13, 2014 3:01 AM, "Nikhil Mahale" <nmah...@nvidia.com> wrote:
> Hi guys, > > This is a xserver issue where timers-list gets corrupted because of race > condition. > nVidia X-driver uses timer to update scanout surface after regular > interval, this timer gets removed from timers list because of this > timers-list corruption and desktop gets freezed. This is only happening > with touch pad because touch pad driver is also heavily using timers, which > is easily triggering this race condition. > > xserver goes through following race condition - > > WaitForSomething() > | > ----> // timers -> synaptics-1 -> nvidia-2 -> null > while (timers && (int) (timers->expires - now) <= 0) > // prototype - DoTimer(OsTimerPtr timer, CARD32 now, > OsTimerPtr *prev) > DoTimer(timers, now, &timers) > | > | > ----> OsBlockSignals(); .... SIGIO OS Signal comes > just before blocking it, > .... > synaptics-1 handler gets called. > // > synaptics-1 gets served and scheduled again; > // timers -> > nvidia-2 -> synaptics-1 -> null > .... > *prev = timer->next; > timer->next = NULL; // timers -> null > // timers list gets corrupted here and > nvidia-2 gets removed from list. > > Attaching patch to fix this issue, its working for me. > > > ** Patch added: "0001-os-Fix-timer-race-conditions.patch" > > https://bugs.launchpad.net/ubuntu/+source/nvidia-prime/+bug/1220426/+attachment/4259702/+files/0001-os-Fix-timer-race-conditions.patch > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1220426 > > Title: > [nvidia-prime]Freeze while using touchpad > > Status in “nvidia-graphics-drivers-319” package in Ubuntu: > Triaged > Status in “nvidia-graphics-drivers-331” package in Ubuntu: > Triaged > Status in “nvidia-graphics-drivers-343” package in Ubuntu: > Triaged > Status in “nvidia-prime” package in Ubuntu: > Triaged > > Bug description: > I'm using an Optimus laptop (Asus N43SL) > nvidia-prime is installed, so my nvidia dedicated graphics card (GT > 540m) is in use. > > Once in a while, my screen will freeze, only when I use my touchpad. > This does not happen with my USB mouse. > This does not happen either when I uninstall nvidia-prime and use my > intel integrated graphics (HD3000). > > I can temporarily solve the issue by doing a VT switch. > > > In the attached Xorg.0.log, you can see "synaptics: ETPS/2 Elantech > Touchpad: touchpad found" each time I did a VT switch and regained control. > > To manage notifications about this bug go to: > > https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-319/+bug/1220426/+subscriptions > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1220426 Title: [nvidia-prime]Freeze while using touchpad To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-319/+bug/1220426/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
