| Message ID | 20190516150957.217157-1-edumazet@google.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | [net] net: avoid weird emergency message | expand |
From: Eric Dumazet <edumazet@google.com> Date: Thu, 16 May 2019 08:09:57 -0700 > 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> Applied, thanks.
diff --git a/net/core/dev.c b/net/core/dev.c index 108ac8137b9be8bc7041b3e49e09c25eeb891d8f..b6b8505cfb3e2394f74b41b8e01055c697ad384b 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -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;
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> --- net/core/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)