net: transition netdev reg state earlier in run_todo

net-next inclusion
from net-next-v5.17-rc5
commit ae68db14
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4VZN0?from=project-issue

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git/commit/?id=ae68db14b6164ce46beffaf35eb7c9bb2f92fee3

--------------------------------

In prep for unregistering netdevs out of order move the netdev
state validation and change outside of the loop.

While at it modernize this code and use WARN() instead of
pr_err() + dump_stack().
Reviewed-by: NEric Dumazet <edumazet@google.com>
Reviewed-by: NXin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/20220215225310.3679266-1-kuba@kernel.orgSigned-off-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NZiyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

net/core/dev.c

@@ -10336,6 +10336,7 @@ static void netdev_wait_allrefs(struct net_device *dev)
  */
 void netdev_run_todo(void)
 {
+	struct net_device *dev, *tmp;
 	struct list_head list;
 #ifdef CONFIG_LOCKDEP
 	struct list_head unlink_list;
@@ -10356,24 +10357,23 @@ void netdev_run_todo(void)
 
 	__rtnl_unlock();
 
-
 	/* Wait for rcu callbacks to finish before next phase */
 	if (!list_empty(&list))
 		rcu_barrier();
 
-	while (!list_empty(&list)) {
-		struct net_device *dev
-			= list_first_entry(&list, struct net_device, todo_list);
-		list_del(&dev->todo_list);
-
+	list_for_each_entry_safe(dev, tmp, &list, todo_list) {
 		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
-			pr_err("network todo '%s' but state %d\n",
-			       dev->name, dev->reg_state);
-			dump_stack();
+			netdev_WARN(dev, "run_todo but not unregistering\n");
+			list_del(&dev->todo_list);
 			continue;
 		}
 
 		dev->reg_state = NETREG_UNREGISTERED;
+	}
+
+	while (!list_empty(&list)) {
+		dev = list_first_entry(&list, struct net_device, todo_list);
+		list_del(&dev->todo_list);
 
 		netdev_wait_allrefs(dev);