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Daniel Vetter d96105a5fe drm: Fix locking for sysfs dpms file ... commit 621bd0f698 upstream. With atomic drivers we need to make sure that (at least in general) property reads hold the right locks. But the legacy dpms property is special and can be read locklessly. Since userspace loves to just randomly look at that all the time (like with "status") do that. To make it clear that we play tricks use the READ_ONCE compiler barrier (and also for paranoia). Note that there's not really anything bad going on since even with the new atomic paths we eventually end up not chasing any pointers (and hence possibly freed memory and other fun stuff). The locking WARNING has been added in commit 88a48e297b Author: Rob Clark <robdclark@gmail.com> Date: Thu Dec 18 16:01:50 2014 -0500 drm: add atomic properties but since drivers are converting not everyone will have seen this from the start. Jens reported this and submitted a patch to just grab the mode_config.connection_mutex, but we can do a bit better. v2: Remove unused variables I failed to git add for real. Reference: http://mid.gmane.org/20150928194822.GA3930@kernel.dk Reported-by: Jens Axboe <axboe@fb.com> Tested-by: Jens Axboe <axboe@fb.com> Cc: Rob Clark <robdclark@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		History 2015-10-27 09:51:53 +09:00
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drm	drm: Fix locking for sysfs dpms file	2015-10-27 09:51:53 +09:00
host1x	gpu: host1x: Export host1x_syncpt_read()	2015-04-02 18:46:20 +02:00
ipu-v3	imx-drm changes to use media bus formats and LDB drm_panel support	2015-04-13 17:28:57 +10:00
vga	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-10-13 16:23:15 +02:00
Makefile	gpu: host1x: Provide a proper struct bus_type	2015-01-27 10:09:14 +01:00