From: Stephane Grosjean <s.grosj...@peak-system.com>
This patch makes atomic the handling of the linux-can echo_skb array and
the network tx queue. This prevents from the "BUG! echo_skb is occupied!"
message to be printed by the linux-can core, in SMP environments.
Reported-by: Diana Burgess <di...@peloton-tech.com>
Signed-off-by: Stephane Grosjean <s.grosj...@peak-system.com>
Cc: linux-stable <sta...@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <m...@pengutronix.de>
---
drivers/net/can/peak_canfd/peak_canfd.c | 12 ++++++------
drivers/net/can/peak_canfd/peak_pciefd_main.c | 8 ++++++--
2 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/net/can/peak_canfd/peak_canfd.c
b/drivers/net/can/peak_canfd/peak_canfd.c
index 55513411a82e..6fa66231ed8e 100644
--- a/drivers/net/can/peak_canfd/peak_canfd.c
+++ b/drivers/net/can/peak_canfd/peak_canfd.c
@@ -262,7 +262,6 @@ static int pucan_handle_can_rx(struct peak_canfd_priv *priv,
spin_lock_irqsave(&priv->echo_lock, flags);
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;
@@ -271,6 +270,7 @@ static int pucan_handle_can_rx(struct peak_canfd_priv *priv,
/* restart tx queue (a slot is free) */
netif_wake_queue(priv->ndev);
+ spin_unlock_irqrestore(&priv->echo_lock, flags);
return 0;
}
@@ -726,11 +726,6 @@ static netdev_tx_t peak_canfd_start_xmit(struct sk_buff
*skb,
*/
should_stop_tx_queue = !!(priv->can.echo_skb[priv->echo_idx]);
- spin_unlock_irqrestore(&priv->echo_lock, flags);
-
- /* write the skb on the interface */
- priv->write_tx_msg(priv, msg);
-
/* stop network tx queue if not enough room to save one more msg too */
if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
should_stop_tx_queue |= (room_left <
@@ -742,6 +737,11 @@ static netdev_tx_t peak_canfd_start_xmit(struct sk_buff
*skb,
if (should_stop_tx_queue)
netif_stop_queue(ndev);
+ spin_unlock_irqrestore(&priv->echo_lock, flags);
+
+ /* write the skb on the interface */
+ priv->write_tx_msg(priv, msg);
+
return NETDEV_TX_OK;
}
diff --git a/drivers/net/can/peak_canfd/peak_pciefd_main.c
b/drivers/net/can/peak_canfd/peak_pciefd_main.c
index 788c3464a3b0..3c51a884db87 100644
--- a/drivers/net/can/peak_canfd/peak_pciefd_main.c
+++ b/drivers/net/can/peak_canfd/peak_pciefd_main.c
@@ -349,8 +349,12 @@ static irqreturn_t pciefd_irq_handler(int irq, void *arg)
priv->tx_pages_free++;
spin_unlock_irqrestore(&priv->tx_lock, flags);
- /* wake producer up */
- netif_wake_queue(priv->ucan.ndev);
+ /* wake producer up (only if enough room in echo_skb array) */
+ spin_lock_irqsave(&priv->ucan.echo_lock, flags);
+ if (!priv->ucan.can.echo_skb[priv->ucan.echo_idx])
+ netif_wake_queue(priv->ucan.ndev);
+
+ spin_unlock_irqrestore(&priv->ucan.echo_lock, flags);
}
/* re-enable Rx DMA transfer for this CAN */
--
2.16.1
