Re: [PATCH] panic during unregister_netdevice()

[Stephen Hemminger <shemminger@osdl.org>]

Try this. Instead of dropping the last reference in unregister, it does it
after all other references are gone (sort of like the old 2.4 code).

diff -Nru a/net/core/dev.c b/net/core/dev.c
--- a/net/core/dev.c	Wed Nov  5 17:04:57 2003
+++ b/net/core/dev.c	Wed Nov  5 17:04:57 2003
@@ -2743,7 +2743,7 @@
 	unsigned long rebroadcast_time, warning_time;
 
 	rebroadcast_time = warning_time = jiffies;
-	while (atomic_read(&dev->refcnt) != 0) {
+	while (atomic_read(&dev->refcnt) > 1) {
 		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
 			rtnl_shlock();
 			rtnl_exlock();
@@ -2838,6 +2838,7 @@
 			dev->reg_state = NETREG_UNREGISTERED;
 
 			netdev_wait_allrefs(dev);
+			dev_put(dev);
 
 			/* paranoia */
 			BUG_ON(atomic_read(&dev->refcnt));
@@ -2974,7 +2975,6 @@
 	/* Finish processing unregister after unlock */
 	net_set_todo(dev);
 
-	dev_put(dev);
 	return 0;
 }