net: avoid weird emergency message

When host is under high stress, it is very possible thread
running netdev_wait_allrefs() returns from msleep(250)
10 seconds late.

This leads to these messages in the syslog :

[...] unregister_netdevice: waiting for syz_tun to become free. Usage count = 0

If the device refcount is zero, the wait is over.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2019-05-16 08:09:57 -07:00 committed by David S. Miller
parent e3a9f61b7e
commit d7c04b05c9
1 changed files with 1 additions and 1 deletions

View File

@ -8927,7 +8927,7 @@ static void netdev_wait_allrefs(struct net_device *dev)
refcnt = netdev_refcnt_read(dev);
if (time_after(jiffies, warning_time + 10 * HZ)) {
if (refcnt && time_after(jiffies, warning_time + 10 * HZ)) {
pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
dev->name, refcnt);
warning_time = jiffies;