From 89b14485caa4b7b2eaf70be0064f0978e68ebeee Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Mon, 4 Jan 2021 21:34:40 +0100 Subject: [PATCH] media: imx: Fix csc/scaler unregister The csc/scaler device private struct is released by ipu_csc_scaler_video_device_release(), which can be called by video_unregister_device() if there are no users of the underlying struct video device. Therefore, the mutex can't be held when calling video_unregister_device() as its memory may be freed by it, leading to a kernel oops. Fortunately, the fix is quite simple as no locking is needed when calling video_unregister_device(): v4l2-core already has its own internal locking, and the structures are also properly refcounted. Fixes: a8ef0488cc59 ("media: imx: add csc/scaler mem2mem device") Signed-off-by: Ezequiel Garcia Reviewed-by: Philipp Zabel Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/staging/media/imx/imx-media-csc-scaler.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/staging/media/imx/imx-media-csc-scaler.c b/drivers/staging/media/imx/imx-media-csc-scaler.c index fab1155..63a0204 100644 --- a/drivers/staging/media/imx/imx-media-csc-scaler.c +++ b/drivers/staging/media/imx/imx-media-csc-scaler.c @@ -869,11 +869,7 @@ void imx_media_csc_scaler_device_unregister(struct imx_media_video_dev *vdev) struct ipu_csc_scaler_priv *priv = vdev_to_priv(vdev); struct video_device *vfd = priv->vdev.vfd; - mutex_lock(&priv->mutex); - video_unregister_device(vfd); - - mutex_unlock(&priv->mutex); } struct imx_media_video_dev * -- 2.7.4