[media] media: saa7146: don’t use mutex_lock_interruptible() in device_release()

Author: Cyril Roelandt <tipecaml@gmail.com>

Use uninterruptible mutex_lock in the release() file op to make sure all
resources are properly freed when a process is being terminated. Returning
-ERESTARTSYS has no effect for a terminating process and this may cause driver
resources not to be released.
This was found using the following semantic patch (http://coccinelle.lip6.fr/):

@r@
identifier fops;
identifier release_func;
@@
static const struct v4l2_file_operations fops = {
.release = release_func
};
@depends on r@
identifier r.release_func;
expression E;
@@
static int release_func(...)
{
...
- if (mutex_lock_interruptible(E)) return -ERESTARTSYS;
+ mutex_lock(E);
...
}


Signed-off-by: Cyril Roelandt 
Acked-by: Hans Verkuil 
Signed-off-by: Mauro Carvalho Chehab 

---
 drivers/media/common/saa7146/saa7146_fops.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)
 
diff --git a/drivers/media/common/saa7146/saa7146_fops.c b/drivers/media/common/saa7146/saa7146_fops.c
index 2652f91..eda01bc 100644
--- a/drivers/media/common/saa7146/saa7146_fops.c
+++ b/drivers/media/common/saa7146/saa7146_fops.c
@@ -265,8 +265,7 @@ static int fops_release(struct file *file)
 
 	DEB_EE("file:%p\n", file);
 
-	if (mutex_lock_interruptible(vdev->lock))
-		return -ERESTARTSYS;
+	mutex_lock(vdev->lock);
 
 	if (vdev->vfl_type == VFL_TYPE_VBI) {
 		if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)