android_kernel_xiaomi_sm8350/net
Johannes Berg bc43b28c10 cfg80211: fix circular lock dependency (1)
Luis reported this lockdep complaint, that he had also
reported earlier but when trying to analyse I had been
locking at the wrong code, and never saw the problem:

(slightly abridged)
=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.31-rc4-wl #6
-------------------------------------------------------
wpa_supplicant/3799 is trying to acquire lock:
 (cfg80211_mutex){+.+.+.}, at: [<ffffffffa009246a>] cfg80211_get_dev_from_ifindex+0x1a/0x90 [cfg80211]

but task is already holding lock:
 (rtnl_mutex){+.+.+.}, at: [<ffffffff81400ff2>] rtnl_lock+0x12/0x20

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.+.}:
       [<ffffffff810857b6>] __lock_acquire+0xd76/0x12b0
       [<ffffffff81085dd3>] lock_acquire+0xe3/0x120
       [<ffffffff814ee7a4>] mutex_lock_nested+0x44/0x350
       [<ffffffff81400ff2>] rtnl_lock+0x12/0x20
       [<ffffffffa009f6a5>] nl80211_send_reg_change_event+0x1f5/0x2a0 [cfg80211]
       [<ffffffffa009529e>] set_regdom+0x28e/0x4c0 [cfg80211]

-> #0 (cfg80211_mutex){+.+.+.}:
       [<ffffffff8108587b>] __lock_acquire+0xe3b/0x12b0
       [<ffffffff81085dd3>] lock_acquire+0xe3/0x120
       [<ffffffff814ee7a4>] mutex_lock_nested+0x44/0x350
       [<ffffffffa009246a>] cfg80211_get_dev_from_ifindex+0x1a/0x90 [cfg80211]
       [<ffffffffa009813f>] get_rdev_dev_by_info_ifindex+0x6f/0xa0 [cfg80211]
       [<ffffffffa009b12b>] nl80211_set_interface+0x3b/0x260 [cfg80211]

When looking at the correct code, the problem is quite
obvious. I'm not entirely sure which code paths lead
here, so until I can analyse it better let's just use
RCU to avoid the problem.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-29 15:45:56 -04:00
..
9p net/9p: Fix crash due to bad mount parameters. 2009-07-02 13:17:01 -07:00
802
8021q vlan: Propagate physical MTU changes 2009-07-20 07:35:37 -07:00
appletalk net: correct off-by-one write allocations reports 2009-06-18 00:29:12 -07:00
atm Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-09 20:18:24 -07:00
ax25 net: Move rx skb_orphan call to where needed 2009-06-23 16:36:25 -07:00
bluetooth net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions 2009-07-05 19:16:04 -07:00
bridge net, bridge: align br_nf_ops assignment 2009-07-05 19:16:14 -07:00
can net/can: add module alias to can protocol drivers 2009-07-15 11:20:38 -07:00
core cfg80211: make aware of net namespaces 2009-07-27 15:24:07 -04:00
dcb
dccp net: adding memory barrier to the poll and receive callbacks 2009-07-09 17:06:57 -07:00
decnet net: remove NET_RX_BAD and NET_RX_CN* defines 2009-07-05 19:15:35 -07:00
dsa dsa: fix 88e6xxx statistics counter snapshotting 2009-07-05 18:03:35 -07:00
econet econet: use NET_RX_SUCCESS instead of magic number 0 for econet_rcv successful return 2009-07-06 18:07:59 -07:00
ethernet
ieee802154 nl802154: add module license and description 2009-06-29 18:20:28 +04:00
ipv4 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-23 19:03:51 -07:00
ipv6 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-23 19:03:51 -07:00
ipx net: correct off-by-one write allocations reports 2009-06-18 00:29:12 -07:00
irda genetlink: make netns aware 2009-07-12 14:03:27 -07:00
iucv net: adding memory barrier to the poll and receive callbacks 2009-07-09 17:06:57 -07:00
key net: correct off-by-one write allocations reports 2009-06-18 00:29:12 -07:00
lapb net: remove NET_RX_BAD and NET_RX_CN* defines 2009-07-05 19:15:35 -07:00
llc net: correct off-by-one write allocations reports 2009-06-18 00:29:12 -07:00
mac80211 mac80211: fix oops due to missing private data 2009-07-27 15:24:19 -04:00
netfilter Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-16 20:21:24 -07:00
netlabel
netlink net/compat/wext: send different messages to compat tasks 2009-07-15 08:53:39 -07:00
netrom net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions 2009-07-05 19:16:04 -07:00
packet af_packet: style cleanups 2009-07-23 18:01:10 -07:00
phonet phonet: phonet_device_get() fix 2009-07-27 08:03:18 -07:00
rds RDS: Refactor end of __conn_create for readability 2009-07-20 08:03:17 -07:00
rfkill Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2009-07-23 19:03:51 -07:00
rose net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions 2009-07-05 19:16:04 -07:00
rxrpc net: adding memory barrier to the poll and receive callbacks 2009-07-09 17:06:57 -07:00
sched net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions 2009-07-05 19:16:04 -07:00
sctp sctp: fix warning at inet_sock_destruct() while release sctp socket 2009-07-06 12:47:08 -07:00
sunrpc sunrpc: Use rcu_barrier() on unload. 2009-06-26 13:51:34 -07:00
tipc genetlink: make netns aware 2009-07-12 14:03:27 -07:00
unix net: adding memory barrier to the poll and receive callbacks 2009-07-09 17:06:57 -07:00
wanrouter
wimax wimax: fix warning caused by not checking retval of rfkill_set_hw_state() 2009-06-11 11:12:48 -07:00
wireless cfg80211: fix circular lock dependency (1) 2009-07-29 15:45:56 -04:00
x25 net: correct off-by-one write allocations reports 2009-06-18 00:29:12 -07:00
xfrm xfrm: use xfrm_addr_cmp() instead of compare addresses directly 2009-06-29 19:41:46 -07:00
compat.c net/compat/wext: send different messages to compat tasks 2009-07-15 08:53:39 -07:00
Kconfig net/compat/wext: send different messages to compat tasks 2009-07-15 08:53:39 -07:00
Makefile net: remove redundant sched/ in net/Makefile 2009-07-12 20:11:14 -07:00
nonet.c
socket.c
sysctl_net.c
TUNABLE