Hi Sakari, Thank you for the patch. On Wed, Dec 20, 2023 at 12:36:54PM +0200, Sakari Ailus wrote: > The parent of the character device related to the media devnode is the > media devnode. Thus the character device needs to be released before the > media devnode's release function. Move it to unregistering of the media > devnode, which mirrors adding the character device in conjunction with > registering the media devnode. > > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > Acked-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> > --- > drivers/media/mc/mc-devnode.c | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/drivers/media/mc/mc-devnode.c b/drivers/media/mc/mc-devnode.c > index 7e22938dfd81..8bc7450ac144 100644 > --- a/drivers/media/mc/mc-devnode.c > +++ b/drivers/media/mc/mc-devnode.c > @@ -51,9 +51,6 @@ static void media_devnode_release(struct device *cd) > > mutex_lock(&media_devnode_lock); > > - /* Delete the cdev on this minor as well */ > - cdev_del(&devnode->cdev); > - > /* Mark device node number as free */ > clear_bit(devnode->minor, media_devnode_nums); Should this be moved to media_devnode_unregister() too ? It can be done in a separate patch. > > @@ -270,6 +267,7 @@ void media_devnode_unregister(struct media_devnode *devnode) > clear_bit(MEDIA_FLAG_REGISTERED, &devnode->flags); > mutex_unlock(&media_devnode_lock); > > + cdev_del(&devnode->cdev); I initially wondered if this could raise with the cdev access in media_open(), as the media_devnode_lock is released just before calling cdev_dev(), but my understanding is that the dev/open race is properly handled in the cdev layer. Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> I wonder if a similar change in v4l2-dev.c would be beneficial. > device_unregister(&devnode->dev); > } > -- Regards, Laurent Pinchart
