github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-23 06:31:58 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

Merge patch series "can: dev: fix can_restart() and replace BUG_ON() by error handling"

Browse Source 
Marc Kleine-Budde <mkl@pengutronix.de> says:

There are 2 BUG_ON() in the CAN dev helpers. During the update/test of
the at91_can driver to rx-offload the one in can_restart() was
triggered, due to a race condition in can_restart() and a hardware
limitation of the at91_can IP core.

This series fixes the race condition, replaces BUG_ON() with an error
message, and does some cleanup. Finally, the BUG_ON() in
can_put_echo_skb() is also replaced with error handling.

Changes in v2:
- 4/5: move "Restarted" debug message and stats after successful restart (Thanks Vincent)
- Link to v1: https://lore.kernel.org/all/20231004-can-dev-fix-can-restart-v1-0-2e52899eaaf5@pengutronix.de

Link: https://lore.kernel.org/all/20231005-can-dev-fix-can-restart-v2-0-91b5c1fd922c@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This commit is contained in:
Marc Kleine-Budde 2023-10-05 21:34:37 +02:00
commit 2f0382a759
2 changed files with 19 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
drivers/net/can/dev/dev.c
View File

@ -132,7 +132,8 @@ static void can_restart(struct net_device *dev)
struct can_frame *cf;
int err;
BUG_ON(netif_carrier_ok(dev));
if (netif_carrier_ok(dev))
netdev_err(dev, "Attempt to restart for bus-off recovery, but carrier is OK?\n");
/* No synchronization needed because the device is bus-off and
* no messages can come in or go out.
@ -141,23 +142,21 @@ static void can_restart(struct net_device *dev)
/* send restart message upstream */
skb = alloc_can_err_skb(dev, &cf);
if (!skb)
goto restart;
cf->can_id |= CAN_ERR_RESTARTED;
netif_rx(skb);
restart:
netdev_dbg(dev, "restarted\n");
priv->can_stats.restarts++;
if (skb) {
cf->can_id |= CAN_ERR_RESTARTED;
netif_rx(skb);
}
/* Now restart the device */
err = priv->do_set_mode(dev, CAN_MODE_START);
netif_carrier_on(dev);
if (err)
netdev_err(dev, "Error %d during restart", err);
err = priv->do_set_mode(dev, CAN_MODE_START);
if (err) {
netdev_err(dev, "Restart failed, error %pe\n", ERR_PTR(err));
netif_carrier_off(dev);
} else {
netdev_dbg(dev, "Restarted\n");
priv->can_stats.restarts++;
}
}
static void can_restart_work(struct work_struct *work)

6
drivers/net/can/dev/skb.c
View File

@ -49,7 +49,11 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
{
struct can_priv *priv = netdev_priv(dev);
BUG_ON(idx >= priv->echo_skb_max);
if (idx >= priv->echo_skb_max) {
netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
__func__, idx, priv->echo_skb_max);
return -EINVAL;
}
/* check flag whether this packet has to be looped back */
if (!(dev->flags & IFF_ECHO) ||