diff mbox series

media: rkvdec: Fix .buf_prepare

Message ID 20210504113714.30612-1-andrzej.p@collabora.com (mailing list archive)
State New, archived
Headers show
Series media: rkvdec: Fix .buf_prepare | expand

Commit Message

Andrzej Pietrasiewicz May 4, 2021, 11:37 a.m. UTC
From: Ezequiel Garcia <ezequiel@collabora.com>

The driver should only set the payload on .buf_prepare if the
buffer is CAPTURE type. If an OUTPUT buffer has a zero bytesused
set by userspace then v4l2-core will set it to buffer length.

Fixes: cd33c830448ba ("media: rkvdec: Add the rkvdec driver")
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>

---
@Hans: I haven't had anyone complain about the issue. The fix is needed for
the rkvdec vp9 work, so I think 5.14 is fine.

 drivers/staging/media/rkvdec/rkvdec.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)


base-commit: 0b276e470a4d43e1365d3eb53c608a3d208cabd4

Comments

Ezequiel Garcia May 4, 2021, 11:56 a.m. UTC | #1
Hi Andrzej,

Thanks a lot for picking this up.

On Tue, 2021-05-04 at 13:37 +0200, Andrzej Pietrasiewicz wrote:
> From: Ezequiel Garcia <ezequiel@collabora.com>
> 
> The driver should only set the payload on .buf_prepare if the
> buffer is CAPTURE type. If an OUTPUT buffer has a zero bytesused
> set by userspace then v4l2-core will set it to buffer length.
> 
> Fixes: cd33c830448ba ("media: rkvdec: Add the rkvdec driver")
> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
> 
> ---
> @Hans: I haven't had anyone complain about the issue. The fix is needed for
> the rkvdec vp9 work, so I think 5.14 is fine.
> 
>  drivers/staging/media/rkvdec/rkvdec.c | 10 +++++++++-
>  1 file changed, 9 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
> index d821661d30f3..ef2166043127 100644
> --- a/drivers/staging/media/rkvdec/rkvdec.c
> +++ b/drivers/staging/media/rkvdec/rkvdec.c
> @@ -481,7 +481,15 @@ static int rkvdec_buf_prepare(struct vb2_buffer *vb)
>                 if (vb2_plane_size(vb, i) < sizeimage)
>                         return -EINVAL;
>         }
> -       vb2_set_plane_payload(vb, 0, f->fmt.pix_mp.plane_fmt[0].sizeimage);
> +
> +       /*
> +        * Buffer bytesused is written by driver for CAPTURE buffers.
> +        * (if userspace passes 0 bytesused for OUTPUT buffers, v4l2-core sets
> +        * it to buffer length).
> +        */
> +       if (!V4L2_TYPE_IS_OUTPUT(vq->type))

Please use V4L2_TYPE_IS_CAPTURE here.

Also, why is this change needed in rkvdec, but not in cedrus
or hantro?

Thanks!
Ezequiel
Andrzej Pietrasiewicz May 5, 2021, 12:17 p.m. UTC | #2
Hi Ezequiel,

W dniu 04.05.2021 o 13:56, Ezequiel Garcia pisze:
> Hi Andrzej,
> 
> Thanks a lot for picking this up.
> 
> On Tue, 2021-05-04 at 13:37 +0200, Andrzej Pietrasiewicz wrote:
>> From: Ezequiel Garcia <ezequiel@collabora.com>
>>
>> The driver should only set the payload on .buf_prepare if the
>> buffer is CAPTURE type. If an OUTPUT buffer has a zero bytesused
>> set by userspace then v4l2-core will set it to buffer length.
>>
>> Fixes: cd33c830448ba ("media: rkvdec: Add the rkvdec driver")
>> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
>> Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
>> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
>>
>> ---
>> @Hans: I haven't had anyone complain about the issue. The fix is needed for
>> the rkvdec vp9 work, so I think 5.14 is fine.
>>
>>   drivers/staging/media/rkvdec/rkvdec.c | 10 +++++++++-
>>   1 file changed, 9 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
>> index d821661d30f3..ef2166043127 100644
>> --- a/drivers/staging/media/rkvdec/rkvdec.c
>> +++ b/drivers/staging/media/rkvdec/rkvdec.c
>> @@ -481,7 +481,15 @@ static int rkvdec_buf_prepare(struct vb2_buffer *vb)
>>                  if (vb2_plane_size(vb, i) < sizeimage)
>>                          return -EINVAL;
>>          }
>> -       vb2_set_plane_payload(vb, 0, f->fmt.pix_mp.plane_fmt[0].sizeimage);
>> +
>> +       /*
>> +        * Buffer bytesused is written by driver for CAPTURE buffers.
>> +        * (if userspace passes 0 bytesused for OUTPUT buffers, v4l2-core sets
>> +        * it to buffer length).
>> +        */
>> +       if (!V4L2_TYPE_IS_OUTPUT(vq->type))
> 
> Please use V4L2_TYPE_IS_CAPTURE here.
> 
> Also, why is this change needed in rkvdec, but not in cedrus
> or hantro?
> 

As a matter of fact I think it is needed in all three, because later on,
whenever a driver uses vb2_get_plane_payload(), without such a patch it
will get an invalid number and write that to a hardware register, causing
incorrect behavior.

I will respond with a v2 series.

Regards,

Andrzej
Andrzej Pietrasiewicz May 5, 2021, 12:23 p.m. UTC | #3
Drivers should only set the payload on .buf_prepare if the
buffer is CAPTURE type. If an OUTPUT buffer has a zero bytesused
set by userspace then v4l2-core will set it to buffer length.

If we overwrite bytesused for OUTPUT buffers, too, then
vb2_get_plane_payload() will return incorrect value which might be then
written to hw registers by the driver.

Andrzej Pietrasiewicz (2):
  media: hantro: Fix .buf_prepare
  media: cedrus: Fix .buf_prepare

Ezequiel Garcia (1):
  media: rkvdec: Fix .buf_prepare

 drivers/staging/media/hantro/hantro_v4l2.c        |  9 ++++++++-
 drivers/staging/media/rkvdec/rkvdec.c             | 10 +++++++++-
 drivers/staging/media/sunxi/cedrus/cedrus_video.c |  8 +++++++-
 3 files changed, 24 insertions(+), 3 deletions(-)


base-commit: 0b276e470a4d43e1365d3eb53c608a3d208cabd4
diff mbox series

Patch

diff --git a/drivers/staging/media/rkvdec/rkvdec.c b/drivers/staging/media/rkvdec/rkvdec.c
index d821661d30f3..ef2166043127 100644
--- a/drivers/staging/media/rkvdec/rkvdec.c
+++ b/drivers/staging/media/rkvdec/rkvdec.c
@@ -481,7 +481,15 @@  static int rkvdec_buf_prepare(struct vb2_buffer *vb)
 		if (vb2_plane_size(vb, i) < sizeimage)
 			return -EINVAL;
 	}
-	vb2_set_plane_payload(vb, 0, f->fmt.pix_mp.plane_fmt[0].sizeimage);
+
+	/*
+	 * Buffer bytesused is written by driver for CAPTURE buffers.
+	 * (if userspace passes 0 bytesused for OUTPUT buffers, v4l2-core sets
+	 * it to buffer length).
+	 */
+	if (!V4L2_TYPE_IS_OUTPUT(vq->type))
+		vb2_set_plane_payload(vb, 0, f->fmt.pix_mp.plane_fmt[0].sizeimage);
+
 	return 0;
 }