4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sudeep Holla <sudeep.holla@xxxxxxx>
commit c61b781ee084e69855477d23dd33e7e6caad652c upstream.
There exists a race when msg_submit return immediately as there was an
active request being processed which may have completed just before it's
checked again in mbox_send_message. This will result in return to the
caller without waiting in mbox_send_message even when it's blocking Tx.
This patch fixes the issue by waiting for the completion always if Tx
is in blocking mode.
Fixes: 2b6d83e2b8b7 ("mailbox: Introduce framework for mailbox")
Reported-by: Alexey Klimov <alexey.klimov@xxxxxxx>
Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
Reviewed-by: Alexey Klimov <alexey.klimov@xxxxxxx>
Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mailbox/mailbox.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -261,7 +261,7 @@ int mbox_send_message(struct mbox_chan *
msg_submit(chan);
- if (chan->cl->tx_block && chan->active_req) {
+ if (chan->cl->tx_block) {
unsigned long wait;
int ret;