Commit d7c04b05 authored May 16, 2019 by Eric Dumazet Committed by David S. Miller May 16, 2019

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>

parent e3a9f61b

net/core/dev.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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;

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