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@xxxxxxxxxxxxx> 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@xxxxxxxxxxxxx> Signed-off-by: Adrian Ratiu <adrian.ratiu@xxxxxxxxxxxxx> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxxxx> --- @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
