From 91785de6f94b58c3fb6664609e3682f011bd28d2 Mon Sep 17 00:00:00 2001 From: Stephane Grosjean Date: Thu, 7 Dec 2017 16:13:43 +0100 Subject: [PATCH] can: peak/pcie_fd: fix potential bug in restarting tx queue Don't rely on can_get_echo_skb() return value to wake the network tx queue up: can_get_echo_skb() returns 0 if the echo array slot was not occupied, but also when the DLC of the released echo frame was 0. Signed-off-by: Stephane Grosjean Cc: linux-stable Signed-off-by: Marc Kleine-Budde --- drivers/net/can/peak_canfd/peak_canfd.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/peak_canfd/peak_canfd.c b/drivers/net/can/peak_canfd/peak_canfd.c index 85268be..5551341 100644 --- a/drivers/net/can/peak_canfd/peak_canfd.c +++ b/drivers/net/can/peak_canfd/peak_canfd.c @@ -258,21 +258,18 @@ static int pucan_handle_can_rx(struct peak_canfd_priv *priv, /* if this frame is an echo, */ if ((rx_msg_flags & PUCAN_MSG_LOOPED_BACK) && !(rx_msg_flags & PUCAN_MSG_SELF_RECEIVE)) { - int n; unsigned long flags; spin_lock_irqsave(&priv->echo_lock, flags); - n = can_get_echo_skb(priv->ndev, msg->client); + can_get_echo_skb(priv->ndev, msg->client); spin_unlock_irqrestore(&priv->echo_lock, flags); /* count bytes of the echo instead of skb */ stats->tx_bytes += cf_len; stats->tx_packets++; - if (n) { - /* restart tx queue only if a slot is free */ - netif_wake_queue(priv->ndev); - } + /* restart tx queue (a slot is free) */ + netif_wake_queue(priv->ndev); return 0; } -- 2.7.4