remoteproc/omap: Check for undefined mailbox messages

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@ti.com>
Signed-off-by: Subramaniam Chanderashekarapuram <subramaniam.ca@ti.com>
Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Andrew F. Davis <afd@ti.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200324110035.29907-10-t-kristo@ti.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/remoteproc/omap_remoteproc.c b/drivers/remoteproc/omap_remoteproc.c
index 604499275896..5bccb5840a02 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);