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 <eduma...@google.com>
Reported-by: syzbot <syzkal...@googlegroups.com>
---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
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;
--
2.21.0.1020.gf2820cf01a-goog
