Daniel Vetter 7abb690a0e drm/i915: Fix spurious -EIO/SIGBUS on wedged gpus ... Chris Wilson noticed that since commit 1f83fee08d [v3.9] Author: Daniel Vetter <daniel.vetter@ffwll.ch> Date: Thu Nov 15 17:17:22 2012 +0100 drm/i915: clear up wedged transitions X can again get -EIO when it does not expect it. And even worse score a SIGBUS when accessing gtt mmaps. The established ABI is that we _only_ return an -EIO from execbuf - all other ioctls should just work. And since the reset code moves all bos out of gpu domains and clears out all the last_seqno/ring tracking there really shouldn't be any reason for non-execbuf code to ever touch the hw and see an -EIO. After some extensive discussions we've noticed that these spurios -EIO are caused by i915_gem_wait_for_error: http://www.mail-archive.com/intel-gfx@lists.freedesktop.org/msg20540.html That is easy to fix by returning 0 instead of -EIO, since grabbing the dev->struct_mutex does not yet mean that we actually want to touch the hw. And so there is no reason at all to fail with -EIO. But that's not the entire since, since often (at least it's easily googleable) dmesg indicates that the reset fails and we declare the gpu wedged. Then, quite a bit later X wakes up with the "Timed out waiting for the gpu reset to complete" DRM_ERROR message in wait_for_errror and brings down the desktop with an -EIO/SIGBUS. So clearly we're missing a wakeup somewhere, since the gpu reset just doesn't take 10 seconds to complete. And indeed we're do handle the terminally wedged state wrong. Fix this all up. References: https://bugs.freedesktop.org/show_bug.cgi?id=63921 References: https://bugs.freedesktop.org/show_bug.cgi?id=64073 Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Damien Lespiau <damien.lespiau@intel.com> Cc: stable@vger.kernel.org Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>		2013-06-03 14:35:18 +02:00
..
drm	drm/i915: Fix spurious -EIO/SIGBUS on wedged gpus	2013-06-03 14:35:18 +02:00
host1x	drivers/gpu/host1x/drm: don't check resource with devm_ioremap_resource	2013-05-18 11:55:30 +02:00
vga	fbcon: fix locking harder	2013-02-08 12:02:43 +10:00
Makefile	gpu: host1x: Add host1x driver	2013-04-22 12:32:40 +02:00