@@ -700,9 +700,9 @@ void media_entity_remove_links(struct media_entity *entity)
if (entity->graph_obj.mdev == NULL)
return;
- mutex_lock(&entity->graph_obj.mdev->graph_mutex);
+ spin_lock(&entity->graph_obj.mdev->lock);
__media_entity_remove_links(entity);
- mutex_unlock(&entity->graph_obj.mdev->graph_mutex);
+ spin_unlock(&entity->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_entity_remove_links);
@@ -792,9 +792,9 @@ int media_entity_setup_link(struct media_link *link, u32 flags)
{
int ret;
- mutex_lock(&link->source->entity->graph_obj.mdev->graph_mutex);
+ spin_lock(&link->source->entity->graph_obj.mdev->lock);
ret = __media_entity_setup_link(link, flags);
- mutex_unlock(&link->source->entity->graph_obj.mdev->graph_mutex);
+ spin_unlock(&link->source->entity->graph_obj.mdev->lock);
return ret;
}
@@ -932,9 +932,9 @@ EXPORT_SYMBOL_GPL(__media_remove_intf_link);
void media_remove_intf_link(struct media_link *link)
{
- mutex_lock(&link->graph_obj.mdev->graph_mutex);
+ spin_lock(&link->graph_obj.mdev->lock);
__media_remove_intf_link(link);
- mutex_unlock(&link->graph_obj.mdev->graph_mutex);
+ spin_unlock(&link->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_remove_intf_link);
@@ -954,8 +954,8 @@ void media_remove_intf_links(struct media_interface *intf)
if (intf->graph_obj.mdev == NULL)
return;
- mutex_lock(&intf->graph_obj.mdev->graph_mutex);
+ spin_lock(&intf->graph_obj.mdev->lock);
__media_remove_intf_links(intf);
- mutex_unlock(&intf->graph_obj.mdev->graph_mutex);
+ spin_unlock(&intf->graph_obj.mdev->lock);
}
EXPORT_SYMBOL_GPL(media_remove_intf_links);
@@ -88,7 +88,7 @@ struct media_device {
struct list_head pads;
struct list_head links;
- /* Protects the entities list */
+ /* Protects the graph objects creation/removal */
spinlock_t lock;
/* Serializes graph operations. */
struct mutex graph_mutex;
Some parts of the media controller are using mutexes while others are using spin locks in order to protect creation and removal of elements in the graph. That's wrong! Also, the V4L2 core can remove graph elements on non-interactive context: BUG: sleeping function called from invalid context at include/linux/sched.h:2776 Fix it by always using spin locks for graph element addition/removal, just like entity creation/removal is protected at media-device.c Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> --- PS.: I'm adding this patch just after "media-device: remove interfaces and interface links". It prevents some troubles with DEBUG_KMEMLEAK and KASAN, with makes them to hang the Kernel during physical device removal (or device driver removal). Without this, we get this error: kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] SMP KASAN drivers/media/media-entity.c | 16 ++++++++-------- include/media/media-device.h | 2 +- 2 files changed, 9 insertions(+), 9 deletions(-)