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| author | Samuel Pitoiset <samuel.pitoiset@gmail.com> | 2015-06-07 22:40:12 +0200 |
|---|---|---|
| committer | Ben Skeggs <bskeggs@redhat.com> | 2015-07-27 18:56:09 +1000 |
| commit | 305c1959ea60ddcae5142a20c50db849a40c2a35 (patch) | |
| tree | d2e6a8f531cef0ec9432e96e50eeef1041acde96 /drivers/gpu | |
| parent | 3693d544056b822f7f2454da5acb7eda9471b902 (diff) | |
| download | linux-305c1959ea60ddcae5142a20c50db849a40c2a35.tar.bz2 | |
drm/nouveau/pm: fix a potential race condition when creating an engine context
There is always the possiblity that the ppm->context pointer would get
partially updated and accidentally would equal ctx. This would allow two
contexts to co-exist, which is not acceptable. Moving the test to the
critical section takes care of this problem.
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c b/drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c index 274457ca3fef..4cf36a3aa814 100644 --- a/drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c +++ b/drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c @@ -358,12 +358,11 @@ nvkm_perfctx_ctor(struct nvkm_object *parent, struct nvkm_object *engine, mutex_lock(&nv_subdev(ppm)->mutex); if (ppm->context == NULL) ppm->context = ctx; - mutex_unlock(&nv_subdev(ppm)->mutex); - if (ctx != ppm->context) - return -EBUSY; + ret = -EBUSY; + mutex_unlock(&nv_subdev(ppm)->mutex); - return 0; + return ret; } struct nvkm_oclass |