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

[xiaolei wang]

Hi Laurent,

Thank you for the review.

On 5/6/26 20:35, Laurent Pinchart wrote:
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> 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@xxxxxxxxxxxxx>
> > Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
> > ---
> >   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
Yes, I'll send a follow-up patch to add v4l2_subdev_cleanup() in the
error paths of mxc_isi_pipe_init() after v4l2_subdev_init_finalize()

succeeds.

thanks

xiaolei

> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> >        media_entity_cleanup(&sd->entity);
> >        mutex_destroy(&pipe->lock);
> >   }
> --
> Regards,
>
> Laurent Pinchart