Hello Philipp,
Thanks for the quick review.
On Mon, 2021-01-04 at 18:16 +0100, Philipp Zabel wrote:
> Hi Ezequiel,
>
> On Mon, 2020-12-28 at 09:21 -0300, Ezequiel Garcia wrote:
> > The csc/scaler device pointer (imxmd->m2m_vdev) is assigned
> > after the imx media device v4l2-async probe completes,
> > therefore we need to check if the device is non-NULL
> > before trying to unregister it.
> >
> > This can be the case if the non-completed imx media device
> > is unbinded (or the driver is removed), leading to a kernel oops.
> >
> > Fixes: a8ef0488cc59 ("media: imx: add csc/scaler mem2mem device")
> > Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxx>
> > ---
> > drivers/staging/media/imx/imx-media-dev.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/staging/media/imx/imx-media-dev.c b/drivers/staging/media/imx/imx-media-dev.c
> > index 6d2205461e56..b6d5f844ad79 100644
> > --- a/drivers/staging/media/imx/imx-media-dev.c
> > +++ b/drivers/staging/media/imx/imx-media-dev.c
> > @@ -107,10 +107,14 @@ static int imx_media_remove(struct platform_device *pdev)
> >
> > v4l2_info(&imxmd->v4l2_dev, "Removing imx-media\n");
> >
> > + if (imxmd->m2m_vdev) {
>
> Thank you, it's even worse. If imx_media_csc_scaler_device_init() fails
> in imx6_media_probe_complete(), imxmd->m2m_vdev contains an error value.
>
> So either this should check
>
> if (!IS_ERR_OR_NULL(imxmd->m2m_vdev))
>
> or (probably better) probe_complete should be changed as well.
>
Good catch. I guess the simplest solution for that is to
clear the m2m_vdev pointer in imx6_media_probe_complete,
if it fails.
Thanks,
Ezequiel
