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authorWolfgang Grandegger <wg@grandegger.com>2016-06-13 15:44:19 +0200
committerWilly Tarreau <w@1wt.eu>2016-08-27 11:40:32 +0200
commit56a5db827f79ab8ed1161d1b2d6d14d2a4d60624 (patch)
tree5f29be00ea700041815bdeb69186432ce219883c /drivers
parent389ca69d3d92b48340928b592b4d80948e284b4c (diff)
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 <wg@grandegger.com> Tested-by: Amr Bekhit <amrbekhit@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Willy Tarreau <w@1wt.eu>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/can/at91_can.c5
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c
index 535d5dd8d816..024078c5fb16 100644
--- a/drivers/net/can/at91_can.c
+++ b/drivers/net/can/at91_can.c
@@ -731,9 +731,10 @@ 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;