Re: [PATCHv7 09/15] remoteproc/omap: Check for undefined mailbox messages

[Mathieu Poirier]

On Fri, Feb 21, 2020 at 12:19:30PM +0200, Tero Kristo wrote:
> From: Suman Anna <s-anna@xxxxxx>
> 
> Add some checks in the mailbox callback function to limit
> any processing in the mailbox callback function to only
> certain currently valid messages, and drop all the remaining
> messages. A debug message is added to print any such invalid
> messages when the appropriate trace control is enabled.
> 
> Co-developed-by: Subramaniam Chanderashekarapuram <subramaniam.ca@xxxxxx>
> Signed-off-by: Subramaniam Chanderashekarapuram <subramaniam.ca@xxxxxx>
> Signed-off-by: Suman Anna <s-anna@xxxxxx>
> Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
> Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>

Acked-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

> ---
>  drivers/remoteproc/omap_remoteproc.c | 6 ++++++
>  drivers/remoteproc/omap_remoteproc.h | 7 +++++++
>  2 files changed, 13 insertions(+)
> 
> diff --git a/drivers/remoteproc/omap_remoteproc.c b/drivers/remoteproc/omap_remoteproc.c
> index 8c3dc0edae95..5d6f32974aa3 100644
> --- a/drivers/remoteproc/omap_remoteproc.c
> +++ b/drivers/remoteproc/omap_remoteproc.c
> @@ -130,6 +130,12 @@ static void omap_rproc_mbox_callback(struct mbox_client *client, void *data)
>  		dev_info(dev, "received echo reply from %s\n", name);
>  		break;
>  	default:
> +		if (msg >= RP_MBOX_READY && msg < RP_MBOX_END_MSG)
> +			return;
> +		if (msg > oproc->rproc->max_notifyid) {
> +			dev_dbg(dev, "dropping unknown message 0x%x", msg);
> +			return;
> +		}
>  		/* msg contains the index of the triggered vring */
>  		if (rproc_vq_interrupt(oproc->rproc, msg) == IRQ_NONE)
>  			dev_dbg(dev, "no message was found in vqid %d\n", msg);
> diff --git a/drivers/remoteproc/omap_remoteproc.h b/drivers/remoteproc/omap_remoteproc.h
> index f6d2036d383d..72f656c93caa 100644
> --- a/drivers/remoteproc/omap_remoteproc.h
> +++ b/drivers/remoteproc/omap_remoteproc.h
> @@ -56,6 +56,12 @@
>   *
>   * @RP_MBOX_ABORT_REQUEST: a "please crash" request, used for testing the
>   * recovery mechanism (to some extent).
> + *
> + * Introduce new message definitions if any here.
> + *
> + * @RP_MBOX_END_MSG: Indicates end of known/defined messages from remote core
> + * This should be the last definition.
> + *
>   */
>  enum omap_rp_mbox_messages {
>  	RP_MBOX_READY		= 0xFFFFFF00,
> @@ -64,6 +70,7 @@ enum omap_rp_mbox_messages {
>  	RP_MBOX_ECHO_REQUEST	= 0xFFFFFF03,
>  	RP_MBOX_ECHO_REPLY	= 0xFFFFFF04,
>  	RP_MBOX_ABORT_REQUEST	= 0xFFFFFF05,
> +	RP_MBOX_END_MSG		= 0xFFFFFF06,
>  };
>  
>  #endif /* _OMAP_RPMSG_H */
> -- 
> 2.17.1
> 
> --
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