Patch "mailbox: handle empty message in tx_tick" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    mailbox: handle empty message in tx_tick

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mailbox-handle-empty-message-in-tx_tick.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From cb710ab1d8a23f68ff8f45aedf3e552bb90e70de Mon Sep 17 00:00:00 2001
From: Sudeep Holla <sudeep.holla@arm.com>
Date: Tue, 21 Mar 2017 11:30:16 +0000
Subject: mailbox: handle empty message in tx_tick

From: Sudeep Holla <sudeep.holla@arm.com>

commit cb710ab1d8a23f68ff8f45aedf3e552bb90e70de upstream.

We already check if the message is empty before calling the client
tx_done callback. Calling completion on a wait event is also invalid
if the message is empty.

This patch moves the existing empty message check earlier.

Fixes: 2b6d83e2b8b7 ("mailbox: Introduce framework for mailbox")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/mailbox/mailbox.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -104,8 +104,11 @@ static void tx_tick(struct mbox_chan *ch
 	/* Submit next message */
 	msg_submit(chan);
 
+	if (!mssg)
+		return;
+
 	/* Notify the client */
-	if (mssg && chan->cl->tx_done)
+	if (chan->cl->tx_done)
 		chan->cl->tx_done(chan->cl, mssg, r);
 
 	if (r != -ETIME && chan->cl->tx_block)


Patches currently in stable-queue which might be from sudeep.holla@arm.com are

queue-4.4/mailbox-always-wait-in-mbox_send_message-for-blocking-tx-mode.patch
queue-4.4/mailbox-skip-complete-wait-event-if-timer-expired.patch
queue-4.4/mailbox-handle-empty-message-in-tx_tick.patch