From: Philipp Zabel Date: Mon, 21 May 2018 10:24:58 +0000 (-0400) Subject: media: uvcvideo: Fix driver reference counting X-Git-Tag: v4.14.79~35 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e75194d294421704baf4c577e504cb9c92ec7ce2;p=platform%2Fkernel%2Flinux-rpi.git media: uvcvideo: Fix driver reference counting commit f9ffcb0a21e1fa8e64d09ed613d884e054ae8191 upstream kref_init initializes the reference count to 1, not 0. This additional reference is never released since the conversion to reference counters. As a result, uvc_delete is not called anymore when UVC cameras are disconnected. Fix this by adding an additional kref_put in uvc_disconnect and in the probe error path. This also allows to remove the temporary additional reference in uvc_unregister_video. Fixes: 9d15cd958c17 ("media: uvcvideo: Convert from using an atomic variable to a reference count") Signed-off-by: Philipp Zabel Reviewed-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sudip Mukherjee Signed-off-by: Sasha Levin --- diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c index 6d22b22cb35b..064d88299adc 100644 --- a/drivers/media/usb/uvc/uvc_driver.c +++ b/drivers/media/usb/uvc/uvc_driver.c @@ -1865,13 +1865,6 @@ static void uvc_unregister_video(struct uvc_device *dev) { struct uvc_streaming *stream; - /* Unregistering all video devices might result in uvc_delete() being - * called from inside the loop if there's no open file handle. To avoid - * that, increment the refcount before iterating over the streams and - * decrement it when done. - */ - kref_get(&dev->ref); - list_for_each_entry(stream, &dev->streams, list) { if (!video_is_registered(&stream->vdev)) continue; @@ -1880,8 +1873,6 @@ static void uvc_unregister_video(struct uvc_device *dev) uvc_debugfs_cleanup_stream(stream); } - - kref_put(&dev->ref, uvc_delete); } static int uvc_register_video(struct uvc_device *dev, @@ -2129,6 +2120,7 @@ static int uvc_probe(struct usb_interface *intf, error: uvc_unregister_video(dev); + kref_put(&dev->ref, uvc_delete); return -ENODEV; } @@ -2146,6 +2138,7 @@ static void uvc_disconnect(struct usb_interface *intf) return; uvc_unregister_video(dev); + kref_put(&dev->ref, uvc_delete); } static int uvc_suspend(struct usb_interface *intf, pm_message_t message)