This is a note to let you know that I've just added the patch titled
net: fec: remove .ndo_poll_controller to avoid deadlocks
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-fec-remove-.ndo_poll_controller-to-avoid-deadloc.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d293d08ce6840b767e34e9e604de692fa2cb3a88
Author: Wei Fang <wei.fang@xxxxxxx>
Date: Sat May 11 14:20:09 2024 +0800
net: fec: remove .ndo_poll_controller to avoid deadlocks
[ Upstream commit c2e0c58b25a0a0c37ec643255558c5af4450c9f5 ]
There is a deadlock issue found in sungem driver, please refer to the
commit ac0a230f719b ("eth: sungem: remove .ndo_poll_controller to avoid
deadlocks"). The root cause of the issue is that netpoll is in atomic
context and disable_irq() is called by .ndo_poll_controller interface
of sungem driver, however, disable_irq() might sleep. After analyzing
the implementation of fec_poll_controller(), the fec driver should have
the same issue. Due to the fec driver uses NAPI for TX completions, the
.ndo_poll_controller is unnecessary to be implemented in the fec driver,
so fec_poll_controller() can be safely removed.
Fixes: 7f5c6addcdc0 ("net/fec: add poll controller function for fec nic")
Signed-off-by: Wei Fang <wei.fang@xxxxxxx>
Link: https://lore.kernel.org/r/20240511062009.652918-1-wei.fang@xxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 7ca8cd78d5574..ca50472479f6d 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -3657,29 +3657,6 @@ fec_set_mac_address(struct net_device *ndev, void *p)
return 0;
}
-#ifdef CONFIG_NET_POLL_CONTROLLER
-/**
- * fec_poll_controller - FEC Poll controller function
- * @dev: The FEC network adapter
- *
- * Polled functionality used by netconsole and others in non interrupt mode
- *
- */
-static void fec_poll_controller(struct net_device *dev)
-{
- int i;
- struct fec_enet_private *fep = netdev_priv(dev);
-
- for (i = 0; i < FEC_IRQ_NUM; i++) {
- if (fep->irq[i] > 0) {
- disable_irq(fep->irq[i]);
- fec_enet_interrupt(fep->irq[i], dev);
- enable_irq(fep->irq[i]);
- }
- }
-}
-#endif
-
static inline void fec_enet_set_netdev_features(struct net_device *netdev,
netdev_features_t features)
{
@@ -3986,9 +3963,6 @@ static const struct net_device_ops fec_netdev_ops = {
.ndo_tx_timeout = fec_timeout,
.ndo_set_mac_address = fec_set_mac_address,
.ndo_eth_ioctl = phy_do_ioctl_running,
-#ifdef CONFIG_NET_POLL_CONTROLLER
- .ndo_poll_controller = fec_poll_controller,
-#endif
.ndo_set_features = fec_set_features,
.ndo_bpf = fec_enet_bpf,
.ndo_xdp_xmit = fec_enet_xdp_xmit,
