Hi Jacopo,
On Mon, Jun 16, 2025 at 06:30:37PM +0200, Jacopo Mondi wrote:
> In order to detect invalid usage pattern such as double list_put()
> calls, add an 'allocated' flag to each display list. Set the flag
> whenever a list is get() and clear it when the list is put(). Warn if a
> list not marked as allocated is returned to the pool of available
> display lists.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/platform/renesas/vsp1/vsp1_dl.c | 11 +++++++++++
> 1 file changed, 11 insertions(+)
>
> diff --git a/drivers/media/platform/renesas/vsp1/vsp1_dl.c b/drivers/media/platform/renesas/vsp1/vsp1_dl.c
> index bb8228b198249943399719b5f37c337fc43eed5b..18617cbb168703b851a9b437fa62f18425934c68 100644
> --- a/drivers/media/platform/renesas/vsp1/vsp1_dl.c
> +++ b/drivers/media/platform/renesas/vsp1/vsp1_dl.c
> @@ -176,6 +176,7 @@ struct vsp1_dl_cmd_pool {
> * @bodies: list of extra display list bodies
> * @pre_cmd: pre command to be issued through extended dl header
> * @post_cmd: post command to be issued through extended dl header
> + * @allocated: flag to detect double list release
> * @has_chain: if true, indicates that there's a partition chain
> * @chain: entry in the display list partition chain
> * @flags: display list flags, a combination of VSP1_DL_FRAME_END_*
> @@ -194,6 +195,8 @@ struct vsp1_dl_list {
> struct vsp1_dl_ext_cmd *pre_cmd;
> struct vsp1_dl_ext_cmd *post_cmd;
>
> + bool allocated;
> +
> bool has_chain;
> struct list_head chain;
>
> @@ -617,6 +620,7 @@ struct vsp1_dl_list *vsp1_dl_list_get(struct vsp1_dl_manager *dlm)
> * display list can assert list_empty() if it is not in a chain.
> */
> INIT_LIST_HEAD(&dl->chain);
> + dl->allocated = true;
> }
>
> spin_unlock_irqrestore(&dlm->lock, flags);
> @@ -657,6 +661,13 @@ static void __vsp1_dl_list_put(struct vsp1_dl_list *dl)
> */
> dl->body0->num_entries = 0;
>
> + /*
> + * Return the display list to the 'free' pool. If the list had already
> + * been returned be loud about it.
> + */
> + WARN_ON_ONCE(!dl->allocated);
> + dl->allocated = false;
> +
> list_add_tail(&dl->list, &dl->dlm->free);
> }
>
--
Regards,
Laurent Pinchart
