https://bugzilla.kernel.org/show_bug.cgi?id=42678 --- Comment #8 from Torsten Kaiser <just.for.lkml@xxxxxxxxxxxxxx> 2012-02-24 08:42:55 --- I think, you're not getting away with blaming userspace. ;-) But this issue is rather complicated, because there is more then one bug / change involved. To summarize the issues: * a change in xf86-video-ati-6.14.2 -> 6.14.3: That was the initial trigger for the GPU lockup messages on my system. While this changes was partly buggy (This has now been fixed, but I think that fix is not released yet) it was merely a trigger for a kernel bug. "Prove" that 6.14.3 is to blame for this: 6.14.2 + kernel 3.1 -> no GPU lockup messages 6.14.3 + kernel 3.1 -> first GPU lockup messages also downgrading to 6.14.2 no longer showed this with later kernels "Prove" that the real bug causing these lockups was a kernel bug: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=1b61925061660009f5b8047f93c5297e04541273 -> with this change 6.14.3 can no longer trigger GPU lockups * the kernel bug causing GPU lockups -> wrong DESKTOP_HEIGHT setup. That was probably always triggerable from userspace, but only the changes in 6.14.3 made this bug visible. This is fixed with above commit 1b61925061660009f5b8047f93c5297e04541273 This bug is not this regression wrt. 3.3-rcX, as I was seeing this since 3.1 * first regression in 3.3-rc1: mutex deadlock that you have already fixed. http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=9fc04b503df9a34ec1a691225445c5b7dfd022e7 * a second, still open regression in 3.3-rc1 that had been masked by the first regression: Even with the mutex fix applied to the kernel (i.e. 3.3-rc2) X was still failing to recover from the GPU lockups. See comment #3 This is the issue, why I would still consider this bug (42678) to be still open. And I think this is a kernel regression and not a userspace issue because: * 6.14.3 (with the GPU lockup trigger) and 3.2 (with the GPU lockup bug) will cause the GPU lockup messages in dmesg, but I did not even notice this was happening at all, because X was always able to recover without noticeable effects. * the same userspace (6.14.3 with the trigger) and 3.3-rc2 (still with the GPU lockup bug, but without the mutex deadlock) will trigger the GPU lockup messages in dmesg, but X will be stuck in the kernel and fail to turn my monitors back on. So I think the stuck X process is caused by the kernel changes between 3.2 and 3.3-rc2. Since 3.3-rc3 X did not get stuck again, but this is because the underlying kernel GPU lockup bug has been fixed, so there never was a need to recover and any recovery bug could no longer be triggered. Does this description of the issues involved make sense for you? Please ask, if I was unclear or messed up my explanation. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
