diff options
author | Cong Wang <amwang@redhat.com> | 2013-01-14 23:34:06 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2013-01-16 15:26:03 -0500 |
commit | f92d318023ff70a273690a91568597168ac32f05 (patch) | |
tree | 91d64d43a5111cfbc689956e27017c144c9205ba /net/core/netpoll.c | |
parent | 7db11f7596e0e54f982b1897f8233056e5c67a7d (diff) | |
download | linux-stable-f92d318023ff70a273690a91568597168ac32f05.tar.gz linux-stable-f92d318023ff70a273690a91568597168ac32f05.tar.bz2 linux-stable-f92d318023ff70a273690a91568597168ac32f05.zip |
netpoll: fix a rtnl lock assertion failure
v4: hold rtnl lock for the whole netpoll_setup()
v3: remove the comment
v2: use RCU read lock
This patch fixes the following warning:
[ 72.013864] RTNL: assertion failed at net/core/dev.c (4955)
[ 72.017758] Pid: 668, comm: netpoll-prep-v6 Not tainted 3.8.0-rc1+ #474
[ 72.019582] Call Trace:
[ 72.020295] [<ffffffff8176653d>] netdev_master_upper_dev_get+0x35/0x58
[ 72.022545] [<ffffffff81784edd>] netpoll_setup+0x61/0x340
[ 72.024846] [<ffffffff815d837e>] store_enabled+0x82/0xc3
[ 72.027466] [<ffffffff815d7e51>] netconsole_target_attr_store+0x35/0x37
[ 72.029348] [<ffffffff811c3479>] configfs_write_file+0xe2/0x10c
[ 72.030959] [<ffffffff8115d239>] vfs_write+0xaf/0xf6
[ 72.032359] [<ffffffff81978a05>] ? sysret_check+0x22/0x5d
[ 72.033824] [<ffffffff8115d453>] sys_write+0x5c/0x84
[ 72.035328] [<ffffffff819789d9>] system_call_fastpath+0x16/0x1b
In case of other races, hold rtnl lock for the entire netpoll_setup() function.
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/netpoll.c')
-rw-r--r-- | net/core/netpoll.c | 24 |
1 files changed, 10 insertions, 14 deletions
diff --git a/net/core/netpoll.c b/net/core/netpoll.c index 9f0506726101..a5ad1c1c4b18 100644 --- a/net/core/netpoll.c +++ b/net/core/netpoll.c @@ -1048,11 +1048,13 @@ int netpoll_setup(struct netpoll *np) struct in_device *in_dev; int err; + rtnl_lock(); if (np->dev_name) - ndev = dev_get_by_name(&init_net, np->dev_name); + ndev = __dev_get_by_name(&init_net, np->dev_name); if (!ndev) { np_err(np, "%s doesn't exist, aborting\n", np->dev_name); - return -ENODEV; + err = -ENODEV; + goto unlock; } if (netdev_master_upper_dev_get(ndev)) { @@ -1066,15 +1068,14 @@ int netpoll_setup(struct netpoll *np) np_info(np, "device %s not up yet, forcing it\n", np->dev_name); - rtnl_lock(); err = dev_open(ndev); - rtnl_unlock(); if (err) { np_err(np, "failed to open %s\n", ndev->name); goto put; } + rtnl_unlock(); atleast = jiffies + HZ/10; atmost = jiffies + carrier_timeout * HZ; while (!netif_carrier_ok(ndev)) { @@ -1094,16 +1095,14 @@ int netpoll_setup(struct netpoll *np) np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n"); msleep(4000); } + rtnl_lock(); } if (!np->local_ip.ip) { if (!np->ipv6) { - rcu_read_lock(); - in_dev = __in_dev_get_rcu(ndev); - + in_dev = __in_dev_get_rtnl(ndev); if (!in_dev || !in_dev->ifa_list) { - rcu_read_unlock(); np_err(np, "no IP address for %s, aborting\n", np->dev_name); err = -EDESTADDRREQ; @@ -1111,14 +1110,12 @@ int netpoll_setup(struct netpoll *np) } np->local_ip.ip = in_dev->ifa_list->ifa_local; - rcu_read_unlock(); np_info(np, "local IP %pI4\n", &np->local_ip.ip); } else { #if IS_ENABLED(CONFIG_IPV6) struct inet6_dev *idev; err = -EDESTADDRREQ; - rcu_read_lock(); idev = __in6_dev_get(ndev); if (idev) { struct inet6_ifaddr *ifp; @@ -1133,7 +1130,6 @@ int netpoll_setup(struct netpoll *np) } read_unlock_bh(&idev->lock); } - rcu_read_unlock(); if (err) { np_err(np, "no IPv6 address for %s, aborting\n", np->dev_name); @@ -1151,17 +1147,17 @@ int netpoll_setup(struct netpoll *np) /* fill up the skb queue */ refill_skbs(); - rtnl_lock(); err = __netpoll_setup(np, ndev, GFP_KERNEL); - rtnl_unlock(); - if (err) goto put; + rtnl_unlock(); return 0; put: dev_put(ndev); +unlock: + rtnl_unlock(); return err; } EXPORT_SYMBOL(netpoll_setup); |