Commit ed7e5a4a authored by Wei Fang's avatar Wei Fang Committed by Liu Chuang
Browse files

net: fec: remove .ndo_poll_controller to avoid deadlocks 

mainline inclusion
from mainline-v6.10-rc1
commit c2e0c58b25a0a0c37ec643255558c5af4450c9f5
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IA6S6S
CVE: CVE-2024-38597

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=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: 7f5c6add ("net/fec: add poll controller function for fec nic")
Signed-off-by: default avatarWei Fang <wei.fang@nxp.com>
Link: https://lore.kernel.org/r/20240511062009.652918-1-wei.fang@nxp.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarLiu Chuang <liuchuang40@huawei.com>
parent 92730d3d

drivers/net/ethernet/freescale/fec_main.c

+0 −26
Original line number Diff line number Diff line
@@ -3208,29 +3208,6 @@ 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)

{
@@ -3304,9 +3281,6 @@ static const struct net_device_ops fec_netdev_ops = { 
	.ndo_tx_timeout		= fec_timeout,

	.ndo_set_mac_address	= fec_set_mac_address,

	.ndo_do_ioctl		= fec_enet_ioctl,

#ifdef CONFIG_NET_POLL_CONTROLLER

	.ndo_poll_controller	= fec_poll_controller,

#endif

	.ndo_set_features	= fec_set_features,

};