android_kernel_msm-6.1_noth.../net
Amerigo Wang 8965779d2c ipv6,mcast: always hold idev->lock before mca_lock
dingtianhong reported the following deadlock detected by lockdep:

 ======================================================
 [ INFO: possible circular locking dependency detected ]
 3.4.24.05-0.1-default #1 Not tainted
 -------------------------------------------------------
 ksoftirqd/0/3 is trying to acquire lock:
  (&ndev->lock){+.+...}, at: [<ffffffff8147f804>] ipv6_get_lladdr+0x74/0x120

 but task is already holding lock:
  (&mc->mca_lock){+.+...}, at: [<ffffffff8149d130>] mld_send_report+0x40/0x150

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #1 (&mc->mca_lock){+.+...}:
        [<ffffffff810a8027>] validate_chain+0x637/0x730
        [<ffffffff810a8417>] __lock_acquire+0x2f7/0x500
        [<ffffffff810a8734>] lock_acquire+0x114/0x150
        [<ffffffff814f691a>] rt_spin_lock+0x4a/0x60
        [<ffffffff8149e4bb>] igmp6_group_added+0x3b/0x120
        [<ffffffff8149e5d8>] ipv6_mc_up+0x38/0x60
        [<ffffffff81480a4d>] ipv6_find_idev+0x3d/0x80
        [<ffffffff81483175>] addrconf_notify+0x3d5/0x4b0
        [<ffffffff814fae3f>] notifier_call_chain+0x3f/0x80
        [<ffffffff81073471>] raw_notifier_call_chain+0x11/0x20
        [<ffffffff813d8722>] call_netdevice_notifiers+0x32/0x60
        [<ffffffff813d92d4>] __dev_notify_flags+0x34/0x80
        [<ffffffff813d9360>] dev_change_flags+0x40/0x70
        [<ffffffff813ea627>] do_setlink+0x237/0x8a0
        [<ffffffff813ebb6c>] rtnl_newlink+0x3ec/0x600
        [<ffffffff813eb4d0>] rtnetlink_rcv_msg+0x160/0x310
        [<ffffffff814040b9>] netlink_rcv_skb+0x89/0xb0
        [<ffffffff813eb357>] rtnetlink_rcv+0x27/0x40
        [<ffffffff81403e20>] netlink_unicast+0x140/0x180
        [<ffffffff81404a9e>] netlink_sendmsg+0x33e/0x380
        [<ffffffff813c4252>] sock_sendmsg+0x112/0x130
        [<ffffffff813c537e>] __sys_sendmsg+0x44e/0x460
        [<ffffffff813c5544>] sys_sendmsg+0x44/0x70
        [<ffffffff814feab9>] system_call_fastpath+0x16/0x1b

 -> #0 (&ndev->lock){+.+...}:
        [<ffffffff810a798e>] check_prev_add+0x3de/0x440
        [<ffffffff810a8027>] validate_chain+0x637/0x730
        [<ffffffff810a8417>] __lock_acquire+0x2f7/0x500
        [<ffffffff810a8734>] lock_acquire+0x114/0x150
        [<ffffffff814f6c82>] rt_read_lock+0x42/0x60
        [<ffffffff8147f804>] ipv6_get_lladdr+0x74/0x120
        [<ffffffff8149b036>] mld_newpack+0xb6/0x160
        [<ffffffff8149b18b>] add_grhead+0xab/0xc0
        [<ffffffff8149d03b>] add_grec+0x3ab/0x460
        [<ffffffff8149d14a>] mld_send_report+0x5a/0x150
        [<ffffffff8149f99e>] igmp6_timer_handler+0x4e/0xb0
        [<ffffffff8105705a>] call_timer_fn+0xca/0x1d0
        [<ffffffff81057b9f>] run_timer_softirq+0x1df/0x2e0
        [<ffffffff8104e8c7>] handle_pending_softirqs+0xf7/0x1f0
        [<ffffffff8104ea3b>] __do_softirq_common+0x7b/0xf0
        [<ffffffff8104f07f>] __thread_do_softirq+0x1af/0x210
        [<ffffffff8104f1c1>] run_ksoftirqd+0xe1/0x1f0
        [<ffffffff8106c7de>] kthread+0xae/0xc0
        [<ffffffff814fff74>] kernel_thread_helper+0x4/0x10

actually we can just hold idev->lock before taking pmc->mca_lock,
and avoid taking idev->lock again when iterating idev->addr_list,
since the upper callers of mld_newpack() already take
read_lock_bh(&idev->lock).

Reported-by: dingtianhong <dingtianhong@huawei.com>
Cc: dingtianhong <dingtianhong@huawei.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Tested-by: Ding Tianhong <dingtianhong@huawei.com>
Tested-by: Chen Weilong <chenweilong@huawei.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01 23:39:21 -07:00
..
9p zero copy error fix 2013-06-10 17:35:25 -07:00
802 net/802/mrp: fix lockdep splat 2013-05-14 13:02:30 -07:00
8021q net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
appletalk net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
atm net: always pass struct netdev_notifier_info to netdevice notifiers 2013-05-28 21:58:54 -07:00
ax25 net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
batman-adv net: Unmap fragment page once iterator is done 2013-06-24 01:46:01 -07:00
bluetooth Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless 2013-06-26 12:01:42 -04:00
bridge bridge: check for zero ether address in fdb add 2013-06-25 16:59:27 -07:00
caif net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
can net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
ceph libceph: must hold mutex for reset_changed_osds() 2013-05-17 12:45:40 -05:00
core Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/shemminger/vxlan-next 2013-07-01 23:17:19 -07:00
dcb rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
dccp tcp: Remove TCPCT 2013-03-17 14:35:13 -04:00
decnet net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
dns_resolver Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-12-16 15:40:50 -08:00
dsa dsa: fix freeing of sparse port allocation 2013-03-25 12:23:41 -04:00
ethernet net: add ETH_P_802_3_MIN 2013-03-28 01:20:42 -04:00
ieee802154 net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
ipv4 vti: remove duplicated code to fix a memory leak 2013-07-01 23:37:14 -07:00
ipv6 ipv6,mcast: always hold idev->lock before mca_lock 2013-07-01 23:39:21 -07:00
ipx net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
irda net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
iucv net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
key xfrm: force a garbage collection after deleting a policy 2013-05-31 17:30:07 -07:00
l2tp l2tp: Fix sendmsg() return value 2013-06-13 02:39:04 -07:00
lapb net/lapb: remove depends on CONFIG_EXPERIMENTAL 2013-01-11 11:40:01 -08:00
llc llc: Fix missing msg_namelen update in llc_ui_recvmsg() 2013-04-07 16:28:01 -04:00
mac80211 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2013-06-28 13:18:21 -04:00
mac802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-30 03:55:20 -04:00
mpls MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
netfilter netfilter: nf_queue: add NFQA_SKB_CSUM_NOTVERIFIED info flag 2013-06-30 18:15:48 +02:00
netlabel net: pass info struct via netdevice notifier 2013-05-28 13:11:01 -07:00
netlink netlink: fix splat in skb_clone with large messages 2013-06-27 22:44:16 -07:00
netrom net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
nfc NFC: llcp: Fix the well known services endianness 2013-06-14 13:45:10 +02:00
openvswitch openvswitch: Add Kconfig dependency on GRE-DEMUX. 2013-07-01 13:19:43 -07:00
packet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-06-19 16:49:39 -07:00
phonet net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
rds net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
rfkill Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2013-04-22 14:58:14 -04:00
rose net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
rxrpc Driver core patches for 3.9-rc1 2013-02-21 12:05:51 -08:00
sched netem: use rb tree to implement the time queue 2013-07-01 18:07:15 -07:00
sctp net: sctp: rework debugging framework to use pr_debug and friends 2013-07-01 23:22:13 -07:00
sunrpc net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
tipc tipc: remove dev_base_lock use from enable_bearer 2013-06-17 15:53:01 -07:00
unix net: Convert uses of typedef ctl_table to struct ctl_table 2013-06-13 02:36:09 -07:00
vmw_vsock VSOCK: Fix VSOCK_HASH and VSOCK_CONN_HASH 2013-06-23 23:51:48 -07:00
wimax
wireless Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2013-06-28 13:18:21 -04:00
x25 x25: Fix broken locking in ioctl error paths. 2013-07-01 18:15:25 -07:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2013-06-26 13:23:13 -07:00
compat.c net: Unbreak compat_sys_{send,recv}msg 2013-06-06 11:52:14 -07:00
Kconfig net: remove NET_LL_RX_POLL config menue 2013-06-17 15:48:14 -07:00
Makefile MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
nonet.c
socket.c net: poll/select low latency socket support 2013-06-25 16:35:52 -07:00
sysctl_net.c