--- Begin Message ---
Hello,
> Hi Strakh:
>
> Thanks for your patch.
>
> But I prefer to remove the mutex_unlock() in the pd_vidioc_s_fmt(),
> since the pd_vidioc_s_fmt() is also called in restore_v4l2_context().
>
> would you please change the patch?
> I will ack it.
>
> Best Regards
> Huang Shijie
>
> 2010/12/13 Alexander Strakh <strakh@xxxxxxxxx>:
> > KERNEL_VERSION: 2.6.36
> > SUBJECT: double mutex_lock in
> > drivers/media/video/tlg2300/pd-video.c in function vidioc_s_fmt
> > SUBSCRIBE:
> > First mutex_unlock in function pd_vidioc_s_fmt in line 767:
> >
> > 764 ret |= send_set_req(pd, VIDEO_ROSOLU_SEL,
> > 765 vid_resol, &cmd_status);
> > 766 if (ret || cmd_status) {
> > 767 mutex_unlock(&pd->lock);
> > 768 return -EBUSY;
> > 769 }
> >
> > Second mutex_unlock in function vidioc_s_fmt in line 806:
> >
> > 805 pd_vidioc_s_fmt(pd, &f->fmt.pix);
> > 806 mutex_unlock(&pd->lock);
> >
> > Found by Linux Device Drivers Verification Project
> >
> > Ðhecks the return code of pd_vidioc_s_fm before mutex_unlocking.
> >
> > Signed-off-by: Alexander Strakh <strakh@xxxxxxxxx>
> >
> > ---
> > diff --git a/drivers/media/video/tlg2300/pd-video.c
> > b/drivers/media/video/tlg2300/pd-video.c
> > index a1ffe18..fe6bd2b 100644
> > --- a/drivers/media/video/tlg2300/pd-video.c
> > +++ b/drivers/media/video/tlg2300/pd-video.c
> > @@ -802,8 +802,8 @@ static int vidioc_s_fmt(struct file *file, void *fh,
> > struct v4l2_format *f)
> > return -EINVAL;
> > }
> >
> > - pd_vidioc_s_fmt(pd, &f->fmt.pix);
> > - mutex_unlock(&pd->lock);
> > + if(!pd_vidioc_s_fmt(pd, &f->fmt.pix))
> > + mutex_unlock(&pd->lock);
> > return 0;
> > }
Removing mutex_unlock from pd_vidioc_s_fmt().
---
diff --git a/drivers/media/video/tlg2300/pd-video.c
b/drivers/media/video/tlg2300/pd-video.c
index a1ffe18..6eb4538 100644
--- a/drivers/media/video/tlg2300/pd-video.c
+++ b/drivers/media/video/tlg2300/pd-video.c
@@ -763,10 +763,8 @@ static int pd_vidioc_s_fmt(struct poseidon *pd, struct
v4l2_pix_format *pix)
}
ret |= send_set_req(pd, VIDEO_ROSOLU_SEL,
vid_resol, &cmd_status);
- if (ret || cmd_status) {
- mutex_unlock(&pd->lock);
+ if (ret || cmd_status)
return -EBUSY;
- }
pix_def->pixelformat = pix->pixelformat; /* save it */
pix->height = (context->tvnormid & V4L2_STD_525_60) ? 480 : 576;
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