Commit 0f7438db authored by Jakub Kicinski's avatar Jakub Kicinski Committed by Zheng Zengkai
Browse files

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: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarXin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/20220215225310.3679266-1-kuba@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarZiyang Xuan <william.xuanziyang@huawei.com>
Reviewed-by: default avatarWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 6597e3ea

net/core/dev.c

+9 −9
Original line number Diff line number Diff line
@@ -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);