If an application that has a driver lock created, wants the lock the
kernel context, it is not allowed to. If the call to drm_lock has a
context of 0, it is rejected. If you set the context to _DRM_LOCK_CONT
then call drm lock, it will pass the context == DRM_KERNEL_CONTEXT checks.
But as the DRM_LOCK_CONT bits are not part of the context id this allows
operations on the DRM_KERNEL_CONTEXT.
Issue: GMINL-7408
Change-Id: I681d6b8d4e5de156b53ca80e0a6f9e72d77b6c06
Signed-off-by: Peter Antoine <peter.antoine@xxxxxxxxx>
---
drivers/gpu/drm/drm_lock.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/drm_lock.c b/drivers/gpu/drm/drm_lock.c
index 80253a7..776f2db 100644
--- a/drivers/gpu/drm/drm_lock.c
+++ b/drivers/gpu/drm/drm_lock.c
@@ -60,7 +60,7 @@ int drm_lock(struct drm_device *dev, void *data, struct drm_file *file_priv)
++file_priv->lock_count;
- if (lock->context == DRM_KERNEL_CONTEXT) {
+ if (_DRM_LOCKING_CONTEXT(lock->context) == DRM_KERNEL_CONTEXT) {
DRM_ERROR("Process %d using kernel context %d\n",
task_pid_nr(current), lock->context);
return -EINVAL;
@@ -150,7 +150,7 @@ int drm_unlock(struct drm_device *dev, void *data, struct drm_file *file_priv)
struct drm_lock *lock = data;
struct drm_master *master = file_priv->master;
- if (lock->context == DRM_KERNEL_CONTEXT) {
+ if (_DRM_LOCKING_CONTEXT(lock->context) == DRM_KERNEL_CONTEXT) {
DRM_ERROR("Process %d using kernel context %d\n",
task_pid_nr(current), lock->context);
return -EINVAL;
--
1.9.1
---------------------------------------------------------------------
Intel Corporation (UK) Limited
Registered No. 1134945 (England)
Registered Office: Pipers Way, Swindon SN3 1RJ
VAT No: 860 2173 47
This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
