[media] em28xx-video: Swap release order to avoid lock nesting

vb2_fop_release might take the video queue mutex lock.
In order to avoid nesting mutexes the private mutex is taken after the
fop_release has finished.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/usb/em28xx/em28xx-video.c b/drivers/media/usb/em28xx/em28xx-video.c
index fc5d60efd4abe99f19acbafff7b83879da5ff3ac..dd19c9ff76e0f9a159c6630320814c89e9e83d5a 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-video.c
+++ b/drivers/media/usb/em28xx/em28xx-video.c
@@ -1664,8 +1664,8 @@ static int em28xx_v4l2_close(struct file *filp)
 
        em28xx_videodbg("users=%d\n", dev->users);
 
-       mutex_lock(&dev->lock);
        vb2_fop_release(filp);
+       mutex_lock(&dev->lock);
 
        if (dev->users == 1) {
                /* the device is already disconnect,