From 3b410a310b48a8e7de3438957635093596ad5ca5 Mon Sep 17 00:00:00 2001
From: Neil Horman <nhorman@tuxdriver.com>
Date: Wed, 13 Oct 2010 16:01:52 +0000
Subject: [PATCH] bonding: Fix netconsole to not deadlock on rmmod
Netconsole calls netpoll_cleanup on receipt of a NETDEVICE_UNREGISTER event.
The notifier subsystem calls these event handlers with rtnl_lock held, which
netpoll_cleanup also takes, resulting in deadlock. Fix this by calling the
__netpoll_cleanup interior function instead, and fixing up the additional
pointers.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/netconsole.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index ca142c47b2e4..94255f09093d 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -678,7 +678,14 @@ static int netconsole_netdev_event(struct notifier_block *this,
strlcpy(nt->np.dev_name, dev->name, IFNAMSIZ);
break;
case NETDEV_UNREGISTER:
- netpoll_cleanup(&nt->np);
+ /*
+ * rtnl_lock already held
+ */
+ if (nt->np.dev) {
+ __netpoll_cleanup(&nt->np);
+ dev_put(nt->np.dev);
+ nt->np.dev = NULL;
+ }
/* Fall through */
case NETDEV_GOING_DOWN:
case NETDEV_BONDING_DESLAVE:
--
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