Tomas Elf 94f7bbe150 drm/i915: Snapshot seqno of most recently submitted request. ... The hang checker needs to inspect whether or not the ring request list is empty as well as if the given engine has reached or passed the most recently submitted request. The problem with this is that the hang checker cannot grab the struct_mutex, which is required in order to safely inspect requests since requests might be deallocated during inspection. In the past we've had kernel panics due to this very unsynchronized access in the hang checker. One solution to this problem is to not inspect the requests directly since we're only interested in the seqno of the most recently submitted request - not the request itself. Instead the seqno of the most recently submitted request is stored separately, which the hang checker then inspects, circumventing the issue of synchronization from the hang checker entirely. This fixes a regression introduced in commit 44cdd6d219 Author: John Harrison <John.C.Harrison@Intel.com> Date: Mon Nov 24 18:49:40 2014 +0000 drm/i915: Convert 'ring_idle()' to use requests not seqnos v2 (Chris Wilson): - Pass current engine seqno to ring_idle() from i915_hangcheck_elapsed() rather than compute it over again. - Remove extra whitespace. Issue: VIZ-5998 Signed-off-by: Tomas Elf <tomas.elf@intel.com> Cc: stable@vger.kernel.org Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> [danvet: Add regressing commit citation provided by Chris.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>		2015-07-13 22:42:39 +02:00
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drm	drm/i915: Snapshot seqno of most recently submitted request.	2015-07-13 22:42:39 +02:00
host1x	gpu: host1x: Export host1x_syncpt_read()	2015-04-02 18:46:20 +02:00
ipu-v3	GPU: ipu: Fix race in installing IPU chained IRQ handler	2015-06-18 14:03:08 +02:00
vga
Makefile	gpu: host1x: Provide a proper struct bus_type	2015-01-27 10:09:14 +01:00