can: fix NOHZ local_softirq_pending 08 warning
When using nanosleep() in an userspace application we get a ratelimit warning
NOHZ: local_softirq_pending 08
for 10 times.
The echo of CAN frames is done from process context and softirq context only.
Therefore the usage of netif_rx() was wrong (for years).
This patch replaces netif_rx() with netif_rx_ni() which has to be used from
process/softirq context. It also adds a missing comment that can_send() must
no be used from hardirq context.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Urs Thuermann <urs@isnogud.escape.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c
index 6971f6c..80ac5631 100644
--- a/drivers/net/can/vcan.c
+++ b/drivers/net/can/vcan.c
@@ -80,7 +80,7 @@
skb->dev = dev;
skb->ip_summed = CHECKSUM_UNNECESSARY;
- netif_rx(skb);
+ netif_rx_ni(skb);
}
static netdev_tx_t vcan_tx(struct sk_buff *skb, struct net_device *dev)
diff --git a/net/can/af_can.c b/net/can/af_can.c
index ef1c43a..6068321 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -199,6 +199,8 @@
* @skb: pointer to socket buffer with CAN frame in data section
* @loop: loopback for listeners on local CAN sockets (recommended default!)
*
+ * Due to the loopback this routine must not be called from hardirq context.
+ *
* Return:
* 0 on success
* -ENETDOWN when the selected interface is down
@@ -278,7 +280,7 @@
}
if (newskb)
- netif_rx(newskb);
+ netif_rx_ni(newskb);
/* update statistics */
can_stats.tx_frames++;
