On Mon, Jun 20, 2022 at 07:55:15PM +0200, Jernej Skrabec wrote: > Now that we have infrastructure for reporting errors, let's add two > checks, which will make sure slice can be actually decoded. > > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxxx> > --- > drivers/staging/media/sunxi/cedrus/cedrus_h265.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c > index cfde4ccf6011..99020b9f9ff8 100644 > --- a/drivers/staging/media/sunxi/cedrus/cedrus_h265.c > +++ b/drivers/staging/media/sunxi/cedrus/cedrus_h265.c Now that you've allowed setup to fail, I would suggest to have some documentation/comments on struct cedrus_dec_ops, to set the expectation/rules for each ops, including the call paths for each operation, which of them are allowed to sleep, etc. > @@ -435,9 +435,17 @@ static int cedrus_h265_setup(struct cedrus_ctx *ctx, struct cedrus_run *run) > * instead of start of slice data. Padding is 8 bits at most (one bit set to 1 and > * at most seven bits set to 0), so we have to inspect only one byte before slice data. > */ > + > + if (slice_params->data_byte_offset == 0) > + return -EOPNOTSUPP; > + AFAICS, cedrus_h265_setup is called from .device_run. We've been discussing control validation before, and I think the ideal place to do that is v4l2_ctrl_ops.s_ctrl, if that's at all possible. Driver's mem2mem device_run are executed in the context of a work_struct and the failure won't really get reported up the stack. > padding = (u8 *)vb2_plane_vaddr(&run->src->vb2_buf, 0) + > slice_params->data_byte_offset - 1; > > + /* at least one bit must be set in that byte */ > + if (*padding == 0) > + return -EINVAL; > + Maybe this is something to check at cedrus_buf_prepare(), when the buffer is queued? Thanks, Ezequiel > for (count = 0; count < 8; count++) > if (*padding & (1 << count)) > break; > -- > 2.36.1 >