From: Wolfgang Grandegger Date: Mon, 13 Jun 2016 13:44:19 +0000 (+0200) Subject: can: at91_can: RX queue could get stuck at high bus load X-Git-Tag: v3.2.82~35 X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=1dcff8d3b5b2eb82f62824ea2197ccc3fcaee8b3 can: at91_can: RX queue could get stuck at high bus load commit 43200a4480cbbe660309621817f54cbb93907108 upstream. At high bus load it could happen that "at91_poll()" enters with all RX message boxes filled up. If then at the end the "quota" is exceeded as well, "rx_next" will not be reset to the first RX mailbox and hence the interrupts remain disabled. Signed-off-by: Wolfgang Grandegger Tested-by: Amr Bekhit Signed-off-by: Marc Kleine-Budde Signed-off-by: Ben Hutchings --- diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c index ab411c3a2b51..a42d75cabd14 100644 --- a/drivers/net/can/at91_can.c +++ b/drivers/net/can/at91_can.c @@ -727,9 +727,10 @@ static int at91_poll_rx(struct net_device *dev, int quota) /* upper group completed, look again in lower */ if (priv->rx_next > get_mb_rx_low_last(priv) && - quota > 0 && mb > get_mb_rx_last(priv)) { + mb > get_mb_rx_last(priv)) { priv->rx_next = get_mb_rx_first(priv); - goto again; + if (quota > 0) + goto again; } return received;