[for-3.18,13/15] mailbox: skip complete wait event if timer expired

Message ID 1501015526-32178-14-git-send-email-amit.pundir@linaro.org
State New
Headers show
Series
  • Stable candidates for 3.18.y
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Commit Message

Amit Pundir July 25, 2017, 8:45 p.m.
From: Sudeep Holla <sudeep.holla@arm.com>


commit cc6eeaa3029a6dbcb4ad41b1f92876483bd88965 upstream.

If a wait_for_completion_timeout() call returns due to a timeout,
complete() can get called after returning from the wait which is
incorrect and can cause subsequent transmissions on a channel to fail.
Since the wait_for_completion_timeout() sees the completion variable
is non-zero caused by the erroneous/spurious complete() call, and
it immediately returns without waiting for the time as expected by the
client.

This patch fixes the issue by skipping complete() call for the timer
expiry.

Fixes: 2b6d83e2b8b7 ("mailbox: Introduce framework for mailbox")
Reported-by: Alexey Klimov <alexey.klimov@arm.com>
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>

---
 drivers/mailbox/mailbox.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

-- 
2.7.4

Patch

diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c
index 2691cb75b2e8..cbde6fccbc29 100644
--- a/drivers/mailbox/mailbox.c
+++ b/drivers/mailbox/mailbox.c
@@ -103,7 +103,7 @@  static void tx_tick(struct mbox_chan *chan, int r)
 	if (mssg && chan->cl->tx_done)
 		chan->cl->tx_done(chan->cl, mssg, r);
 
-	if (chan->cl->tx_block)
+	if (r != -ETIME && chan->cl->tx_block)
 		complete(&chan->tx_complete);
 }
 
@@ -266,8 +266,8 @@  int mbox_send_message(struct mbox_chan *chan, void *mssg)
 
 		ret = wait_for_completion_timeout(&chan->tx_complete, wait);
 		if (ret == 0) {
-			t = -EIO;
-			tx_tick(chan, -EIO);
+			t = -ETIME;
+			tx_tick(chan, t);
 		}
 	}