From: Ezequiel Garcia ezequiel@collabora.com
[ Upstream commit 89b14485caa4b7b2eaf70be0064f0978e68ebeee ]
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 ezequiel@collabora.com Reviewed-by: Philipp Zabel p.zabel@pengutronix.de Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+huawei@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 2b635ebf62d6a..a15d970adb983 100644 --- a/drivers/staging/media/imx/imx-media-csc-scaler.c +++ b/drivers/staging/media/imx/imx-media-csc-scaler.c @@ -866,11 +866,7 @@ 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 *