Amerigo Wang 3ef208a71f ipv6,mcast: always hold idev->lock before mca_lock ... [ Upstream commit 8965779d2c, with some bits from commit b7b1bfce0b ("ipv6: split duplicate address detection and router solicitation timer") to get the __ipv6_get_lladdr() used by this patch. ] 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2013-07-28 16:26:02 -07:00
..
9p	9p: Reduce object size with CONFIG_NET_9P_DEBUG	2012-01-05 10:51:44 -06:00
bluetooth	Bluetooth: Fix mgmt handling of power on failures	2013-06-20 11:58:44 -07:00
caif	caif-hsi: Add RX flip buffer	2012-02-04 16:06:28 -05:00
irda
iucv	af_iucv: add shutdown for HS transport	2012-03-07 22:52:24 -08:00
netfilter	netfilter: nf_conntrack: fix racy timer handling with reliable events	2012-10-21 09:28:00 -07:00
netns	BUG: headers with BUG/BUG_ON etc. need linux/bug.h	2012-03-04 17:54:34 -05:00
nfc	NFC: NCI code identation fixes	2012-03-06 15:16:25 -05:00
phonet	net: dont hold rtnl mutex during netlink dump callbacks	2011-05-02 15:26:28 -07:00
sctp	sctp: check cached dst before using it	2012-05-10 23:15:47 -04:00
tc_act
act_api.h	net: sched: constify tcf_proto and tc_action	2011-07-06 02:52:16 -07:00
addrconf.h	ipv6,mcast: always hold idev->lock before mca_lock	2013-07-28 16:26:02 -07:00
af_ieee802154.h
af_rxrpc.h	net: Remove __KERNEL__ cpp checks from include/net	2011-04-24 10:54:56 -07:00
af_unix.h	switch unix_sock to struct path	2012-03-20 21:29:41 -04:00
ah.h
arp.h	ipv4: Eliminate spurious argument to __ipv4_neigh_lookup	2012-02-15 17:48:35 -05:00
atmclip.h	atm: clip: Use device neigh support on top of "arp_tbl".	2011-11-30 18:51:03 -05:00
ax25.h	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
ax88796.h
cfg80211-wext.h	cfg80211: remove unused wext handler exports	2011-08-08 14:26:29 -04:00
cfg80211.h	mac80211: verify that skb data is present	2012-11-17 13:16:11 -08:00
checksum.h
cipso_ipv4.h	cipso: handle CIPSO options correctly when NetLabel is disabled	2012-07-16 09:03:44 -07:00
cls_cgroup.h
compat.h	net: get rid of some pointless casts to sockaddr	2012-03-11 19:11:22 -07:00
datalink.h
dcbevent.h	dcb: Add stub routines for !CONFIG_DCB	2011-10-06 15:49:51 -04:00
dcbnl.h	net: dcb: getnumtcs()/setnumtcs() should return an int	2012-03-02 18:16:49 -08:00
dn.h	decnet: net/dn.h needs net/flow.h	2012-02-15 16:37:44 -05:00
dn_dev.h
dn_fib.h
dn_neigh.h
dn_nsp.h
dn_route.h
dsa.h	dsa: Include linux/if_ether.h to fix build error	2011-12-01 11:41:06 -05:00
dsfield.h
dst.h	ipv6: fix incorrect ipsec fragment	2012-06-10 00:36:15 +09:00
dst_ops.h	net: Rename the dst_opt default_mtu method to mtu	2011-11-26 14:29:50 -05:00
esp.h
ethoc.h
fib_rules.h
flow.h	ipv4: reset flowi parameters on route connect	2012-02-04 19:29:48 -05:00
flow_keys.h	flow_dissector: use a 64bit load/store	2011-11-29 13:17:03 -05:00
garp.h	garp: remove last synchronize_rcu() call	2011-05-12 17:46:56 -04:00
gen_stats.h
genetlink.h	net: Deinline __nlmsg_put and genlmsg_put. -7k code on i386 defconfig.	2012-01-30 15:22:06 -05:00
gre.h
icmp.h	ipv4: reduce percpu needs for icmpmsg mibs	2011-11-09 16:04:20 -05:00
ieee80211_radiotap.h	wireless: move ieee80211chan2mhz macro	2011-11-11 12:32:50 -05:00
ieee802154.h	6LoWPAN: add fragmentation support	2011-11-14 00:19:42 -05:00
ieee802154_netdev.h
if_inet6.h	ipv6: updates to privacy addresses per RFC 4941.	2011-08-01 18:05:00 -07:00
inet6_connection_sock.h	inet: Pass flowi to ->queue_xmit().	2011-05-08 15:28:28 -07:00
inet6_hashtables.h	ipv6: use a stronger hash for tcp	2013-02-28 06:59:06 -08:00
inet_common.h
inet_connection_sock.h	inet: Fix kmemleak in tcp_v4/6_syn_recv_sock and dccp_v4/6_request_recv_sock	2013-01-11 09:07:14 -08:00
inet_ecn.h	inet: add rfc 3168 extract in front of INET_ECN_encapsulate()	2011-10-22 01:25:23 -04:00
inet_frag.h	inet: limit length of fragment queue hash table bucket lists	2013-03-28 12:11:54 -07:00
inet_hashtables.h	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
inet_sock.h	ipv6: use a stronger hash for tcp	2013-02-28 06:59:06 -08:00
inet_timewait_sock.h	inet: remove rcu protection on tw_net	2011-12-14 13:34:55 -05:00
inetpeer.h	inetpeer: fix a race in inetpeer_gc_worker()	2012-07-16 09:03:45 -07:00
ip.h	ipv4: Make ip_call_ra_chain() return bool.	2012-03-09 14:34:50 -08:00
ip6_checksum.h
ip6_fib.h	ipv6: clean up rt6_clean_expires	2012-04-17 22:31:59 -04:00
ip6_route.h	Merge branch 'nf-next' of git://1984.lsi.us.es/net-next	2011-12-25 02:21:45 -05:00
ip6_tunnel.h
ip_fib.h	ipv4: fix definition of FIB_TABLE_HASHSZ	2013-03-28 12:11:53 -07:00
ip_vs.h	ipvs: fix oops on NAT reply in br_nf context	2012-10-21 09:28:00 -07:00
ipcomp.h
ipconfig.h
ipip.h
ipv6.h	ipv6: use a stronger hash for tcp	2013-02-28 06:59:06 -08:00
ipx.h	net: Remove __KERNEL__ cpp checks from include/net	2011-04-24 10:54:56 -07:00
iw_handler.h
lapb.h	wan: make LAPB callbacks const	2011-09-16 19:20:20 -04:00
lib80211.h	include: replace linux/module.h with "struct module" wherever possible	2011-10-31 19:32:32 -04:00
llc.h	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
llc_c_ac.h
llc_c_ev.h
llc_c_st.h
llc_conn.h
llc_if.h
llc_pdu.h	bonding,llc: Fix structure sizeof incompatibility for some PDUs	2011-05-13 15:13:24 -04:00
llc_s_ac.h
llc_s_ev.h
llc_s_st.h
llc_sap.h
mac80211.h	mac80211: Convert WARN_ON to WARN_ON_ONCE	2012-04-09 15:54:48 -04:00
mip6.h
mld.h
ndisc.h	ipv6: Remove neigh argument from ndisc_send_redirect()	2012-01-27 21:00:08 -05:00
neighbour.h	ipv6: Use universal hash for NDISC.	2011-12-28 15:06:58 -05:00
net_namespace.h	net: use IS_ENABLED(CONFIG_IPV6)	2011-12-11 18:25:16 -05:00
net_ratelimit.h	net: Kill ratelimit.h dependency in linux/net.h	2011-05-27 13:41:33 -04:00
netdma.h
netevent.h	net: Remove __KERNEL__ cpp checks from include/net	2011-04-24 10:54:56 -07:00
netlabel.h	doc: Update the email address for Paul Moore in various source files	2011-08-01 17:58:33 -07:00
netlink.h	net: Deinline __nlmsg_put and genlmsg_put. -7k code on i386 defconfig.	2012-01-30 15:22:06 -05:00
netprio_cgroup.h	netprio_cgroup: fix wrong memory access when NETPRIO_CGROUP=m	2012-02-10 15:08:57 -05:00
netrom.h
nexthop.h
nl802154.h
p8022.h
ping.h	net: ping: fix build failure	2011-05-17 14:16:58 -04:00
pkt_cls.h
pkt_sched.h	net: sched: constify tcf_proto and tc_action	2011-07-06 02:52:16 -07:00
protocol.h	net: use IS_ENABLED(CONFIG_IPV6)	2011-12-11 18:25:16 -05:00
psnap.h
raw.h
rawv6.h	net: Remove __KERNEL__ cpp checks from include/net	2011-04-24 10:54:56 -07:00
red.h	net_sched: red: Make minor corrections to comments	2012-04-16 23:53:11 -04:00
regulatory.h	cfg80211: pass DFS region to drivers through reg_notifier()	2011-11-21 16:20:41 -05:00
request_sock.h	tcp: Change possible SYN flooding messages	2011-09-15 14:49:43 -04:00
rose.h
route.h	ipv4: reset flowi parameters on route connect	2012-02-04 19:29:48 -05:00
rtnetlink.h	rtnetlink: Fix problem with buffer allocation	2012-02-21 16:56:45 -05:00
sch_generic.h	bonding: Fix corrupted queue_mapping	2012-07-16 09:03:47 -07:00
scm.h	net: fix incorrect credentials passing	2013-05-01 09:41:16 -07:00
secure_seq.h	tcp: add const qualifiers where possible	2011-10-21 05:22:42 -04:00
slhc_vj.h
snmp.h	Merge branch 'for-3.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2012-01-09 13:08:28 -08:00
sock.h	ipv6: do not clear pinet6 field	2013-05-19 10:54:47 -07:00
stp.h
tcp.h	tcp: force a dst refcount when prequeue packet	2013-05-19 10:54:43 -07:00
tcp_memcontrol.h	cgroup: remove cgroup_subsys argument from callbacks	2012-02-02 09:20:22 -08:00
tcp_states.h
timewait_sock.h	BUG: headers with BUG/BUG_ON etc. need linux/bug.h	2012-03-04 17:54:34 -05:00
transp_v6.h	net: relax PKTINFO non local ipv6 udp xmit check	2011-08-30 17:39:01 -04:00
udp.h	BUG: headers with BUG/BUG_ON etc. need linux/bug.h	2012-03-04 17:54:34 -05:00
udplite.h	net: ipv4: Standardize prefixes for message logging	2012-03-12 17:05:21 -07:00
wext.h
wimax.h	net: wimax: Remove of unused 'rfkill_input' pointer	2011-06-24 17:50:44 -07:00
wpan-phy.h	BUG: headers with BUG/BUG_ON etc. need linux/bug.h	2012-03-04 17:54:34 -05:00
x25.h
x25device.h
xfrm.h	xfrm: Workaround incompatibility of ESN and async crypto	2012-10-13 05:38:40 +09:00