Re: [PATCH v2 2/4] media: imx8-isi: add missing v4l2_subdev_cleanup() in crossbar and pipe

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hello Xiaolei,

Thank you for the patch.

On Wed, May 06, 2026 at 11:12:08AM +0800, Xiaolei Wang wrote:
> Both mxc_isi_crossbar_init() and mxc_isi_pipe_init() call
> v4l2_subdev_init_finalize() which allocates the subdev active state,
> but neither mxc_isi_crossbar_cleanup() nor mxc_isi_pipe_cleanup()
> calls v4l2_subdev_cleanup() to free it.
> 
> This causes a memory leak on every rmmod, reported by kmemleak:
> 
>   unreferenced object 0xffff0000d06fc800 (size 192):
>     comm "(udev-worker)", pid 254, jiffies 4294913455
>     backtrace (crc 36eeae58):
>       kmemleak_alloc+0x34/0x40
>       __kvmalloc_node_noprof+0x5f8/0x7d8
>       __v4l2_subdev_state_alloc+0x1fc/0x30c
>       __v4l2_subdev_init_finalize+0x178/0x368
> 
> Add the missing v4l2_subdev_cleanup() calls before media_entity_cleanup()
> in both crossbar and pipe cleanup paths.
> 
> Fixes: cf21f328fcaf ("media: nxp: Add i.MX8 ISI driver")
> Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
> Reviewed-by: Frank Li <Frank.Li@nxp.com>
> ---
>  drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c | 1 +
>  drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c     | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> index 605a45124103..c580c831972e 100644
> --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-crossbar.c
> @@ -491,6 +491,7 @@ int mxc_isi_crossbar_init(struct mxc_isi_dev *isi)
>  
>  void mxc_isi_crossbar_cleanup(struct mxc_isi_crossbar *xbar)
>  {
> +	v4l2_subdev_cleanup(&xbar->sd);
>  	media_entity_cleanup(&xbar->sd.entity);
>  	kfree(xbar->pads);
>  	kfree(xbar->inputs);
> diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c
> index a41c51dd9ce0..cb50af2270f6 100644
> --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c
> +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-pipe.c
> @@ -819,6 +819,7 @@ void mxc_isi_pipe_cleanup(struct mxc_isi_pipe *pipe)
>  {
>  	struct v4l2_subdev *sd = &pipe->sd;
>  
> +	v4l2_subdev_cleanup(sd);

v4l2_subdev_cleanup() should also be called in some of the error paths
of mxc_isi_pipe_init(). This can be done in a separate patch, so

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

>  	media_entity_cleanup(&sd->entity);
>  	mutex_destroy(&pipe->lock);
>  }

-- 
Regards,

Laurent Pinchart