From d2ccd0560d9648a98ae0c6534588144044cff0a0 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Tue, 1 Apr 2025 09:34:42 -0700 Subject: [PATCH] net: switch to netif_disable_lro in inetdev_init Cosmin reports the following deadlock: dump_stack_lvl+0x62/0x90 print_deadlock_bug+0x274/0x3b0 __lock_acquire+0x1229/0x2470 lock_acquire+0xb7/0x2b0 __mutex_lock+0xa6/0xd20 dev_disable_lro+0x20/0x80 inetdev_init+0x12f/0x1f0 inetdev_event+0x48b/0x870 notifier_call_chain+0x38/0xf0 netif_change_net_namespace+0x72e/0x9f0 do_setlink.isra.0+0xd5/0x1220 rtnl_newlink+0x7ea/0xb50 rtnetlink_rcv_msg+0x459/0x5e0 netlink_rcv_skb+0x54/0x100 netlink_unicast+0x193/0x270 netlink_sendmsg+0x204/0x450 Switch to netif_disable_lro which assumes the caller holds the instance lock. inetdev_init is called for blackhole device (which sw device and doesn't grab instance lock) and from REGISTER/UNREGISTER notifiers. We already hold the instance lock for REGISTER notifier during netns change and we'll soon hold the lock during other paths. Reviewed-by: Jakub Kicinski Reported-by: Cosmin Ratiu Fixes: ad7c7b2172c3 ("net: hold netdev instance lock during sysfs operations") Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250401163452.622454-2-sdf@fomichev.me Signed-off-by: Jakub Kicinski --- net/ipv4/devinet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 754f60fb6e25..77e5705ac799 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -281,7 +281,7 @@ static struct in_device *inetdev_init(struct net_device *dev) if (!in_dev->arp_parms) goto out_kfree; if (IPV4_DEVCONF(in_dev->cnf, FORWARDING)) - dev_disable_lro(dev); + netif_disable_lro(dev); /* Reference in_dev->dev */ netdev_hold(dev, &in_dev->dev_tracker, GFP_KERNEL); /* Account for reference dev->ip_ptr (below) */ -- 2.49.0