linux_dsm_epyc7002/net
Emmanuel Grumbach 8ffcc704c9 mac80211: avoid deadlock revealed by lockdep
sdata->u.ap.request_smps_work can’t be flushed synchronously
under wdev_lock(wdev) since ieee80211_request_smps_ap_work
itself locks the same lock.
While at it, reset the driver_smps_mode when the ap is
stopped to its default: OFF.

This solves:

======================================================
[ INFO: possible circular locking dependency detected ]
3.12.0-ipeer+ #2 Tainted: G           O
-------------------------------------------------------
rmmod/2867 is trying to acquire lock:
  ((&sdata->u.ap.request_smps_work)){+.+...}, at: [<c105b8d0>] flush_work+0x0/0x90

but task is already holding lock:
  (&wdev->mtx){+.+.+.}, at: [<f9b32626>] cfg80211_stop_ap+0x26/0x230 [cfg80211]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&wdev->mtx){+.+.+.}:
        [<c10aefa9>] lock_acquire+0x79/0xe0
        [<c1607a1a>] mutex_lock_nested+0x4a/0x360
        [<fb06288b>] ieee80211_request_smps_ap_work+0x2b/0x50 [mac80211]
        [<c105cdd8>] process_one_work+0x198/0x450
        [<c105d469>] worker_thread+0xf9/0x320
        [<c10669ff>] kthread+0x9f/0xb0
        [<c1613397>] ret_from_kernel_thread+0x1b/0x28

-> #0 ((&sdata->u.ap.request_smps_work)){+.+...}:
        [<c10ae9df>] __lock_acquire+0x183f/0x1910
        [<c10aefa9>] lock_acquire+0x79/0xe0
        [<c105b917>] flush_work+0x47/0x90
        [<c105d867>] __cancel_work_timer+0x67/0xe0
        [<c105d90f>] cancel_work_sync+0xf/0x20
        [<fb0765cc>] ieee80211_stop_ap+0x8c/0x340 [mac80211]
        [<f9b3268c>] cfg80211_stop_ap+0x8c/0x230 [cfg80211]
        [<f9b0d8f9>] cfg80211_leave+0x79/0x100 [cfg80211]
        [<f9b0da72>] cfg80211_netdev_notifier_call+0xf2/0x4f0 [cfg80211]
        [<c160f2c9>] notifier_call_chain+0x59/0x130
        [<c106c6de>] __raw_notifier_call_chain+0x1e/0x30
        [<c106c70f>] raw_notifier_call_chain+0x1f/0x30
        [<c14f8213>] call_netdevice_notifiers_info+0x33/0x70
        [<c14f8263>] call_netdevice_notifiers+0x13/0x20
        [<c14f82a4>] __dev_close_many+0x34/0xb0
        [<c14f83fe>] dev_close_many+0x6e/0xc0
        [<c14f9c77>] rollback_registered_many+0xa7/0x1f0
        [<c14f9dd4>] unregister_netdevice_many+0x14/0x60
        [<fb06f4d9>] ieee80211_remove_interfaces+0xe9/0x170 [mac80211]
        [<fb055116>] ieee80211_unregister_hw+0x56/0x110 [mac80211]
        [<fa3e9396>] iwl_op_mode_mvm_stop+0x26/0xe0 [iwlmvm]
        [<f9b9d8ca>] _iwl_op_mode_stop+0x3a/0x70 [iwlwifi]
        [<f9b9d96f>] iwl_opmode_deregister+0x6f/0x90 [iwlwifi]
        [<fa405179>] __exit_compat+0xd/0x19 [iwlmvm]
        [<c10b8bf9>] SyS_delete_module+0x179/0x2b0
        [<c1613421>] sysenter_do_call+0x12/0x32

Fixes: 687da13223 ("mac80211: implement SMPS for AP")
Cc: <stable@vger.kernel.org> [3.13]
Reported-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-06 09:55:18 +01:00
..
9p net/9p: remove virtio default hack and set appropriate bits instead 2013-11-23 16:13:36 -06:00
802 neigh: use NEIGH_VAR_INIT in ndo_neigh_setup functions. 2014-01-16 11:31:58 -08:00
8021q 8021q: Use ether_addr_copy 2014-01-21 18:13:04 -08:00
appletalk net: Fix some fallout from the etner_addr_copy() changes. 2014-01-21 18:57:26 -08:00
atm net: Fix some fallout from the etner_addr_copy() changes. 2014-01-21 18:57:26 -08:00
ax25 net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-01-18 00:55:41 -08:00
bluetooth net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
bridge bridge: Remove unnecessary vlan_put_tag in br_handle_vlan 2014-01-22 21:29:27 -08:00
caif net: Missing change from the ether_addr_copy() fixups. 2014-01-21 22:54:01 -08:00
can net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
ceph Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
core net: Fix warning on make htmldocs caused by skbuff.c 2014-01-28 18:06:06 -08:00
dcb dcb: use __dev_get_by_name instead of dev_get_by_name to find interface 2014-01-14 18:50:46 -08:00
dccp ipv4: introduce hardened ip_no_pmtu_disc mode 2014-01-13 11:22:55 -08:00
decnet net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
dns_resolver net/*: Fix FSF address in file headers 2013-12-06 12:37:57 -05:00
dsa dsa: Use ether_addr_copy 2014-01-21 18:13:05 -08:00
ethernet net: eth_type_trans() should use skb_header_pointer() 2014-01-16 15:30:31 -08:00
hsr net/hsr: using kfree_rcu() to simplify the code 2013-12-17 16:32:30 -05:00
ieee802154 net: 6lowpan: fixup for code movement 2014-01-27 16:43:03 -08:00
ipv4 net: gre: use icmp_hdr() to get inner ip header 2014-01-27 20:38:26 -08:00
ipv6 net: Fix memory leak if TPROXY used with TCP early demux 2014-01-27 16:22:11 -08:00
ipx net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
irda net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
iucv net: rework recvmsg handler msg_name and msg_namelen logic 2013-11-20 21:52:30 -05:00
key xfrm: export verify_userspi_info for pkfey and netlink interface 2013-12-16 12:54:02 +01:00
l2tp ipv6: protect protocols not handling ipv4 from v4 connection/bind attempts 2014-01-21 16:59:19 -08:00
lapb net/lapb: re-send packets on timeout 2013-09-23 16:52:45 -04:00
llc llc: remove noisy WARN from llc_mac_hdr_init 2014-01-28 18:01:32 -08:00
mac80211 mac80211: avoid deadlock revealed by lockdep 2014-02-06 09:55:18 +01:00
mac802154 mac802154: fix following checkpath.pl warning Prefer pr_warn(... to pr_warning(... 2013-12-22 18:53:08 -05:00
mpls ipip: add GSO/TSO support 2013-10-19 19:36:19 -04:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
netlabel netlabel: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
netlink net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
netrom net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
openvswitch net: replace macros net_random and net_srandom with direct calls to prandom 2014-01-14 15:15:25 -08:00
packet af_packet: Add Queue mapping mode to af_packet fanout operation 2014-01-22 17:35:50 -08:00
phonet net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
rds net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
rfkill Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
rose net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
rxrpc RxRPC fixes 2014-01-28 18:04:18 -08:00
sched net: add and use skb_gso_transport_seglen() 2014-01-26 22:38:23 -08:00
sctp sctp: remove macros sctp_bh_[un]lock_sock 2014-01-21 18:41:36 -08:00
sunrpc Merge branch 'for-3.14' of git://linux-nfs.org/~bfields/linux 2014-01-30 10:18:43 -08:00
tipc net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
unix net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
vmw_vsock net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
wimax wimax: remove dead code 2013-11-21 13:09:42 -05:00
wireless cfg80211: re-enable 5/10 MHz support 2014-02-06 09:55:18 +01:00
x25 net: add build-time checks for msg->msg_name size 2014-01-18 23:04:16 -08:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
compat.c net: clamp ->msg_namelen instead of returning an error 2013-11-29 16:12:52 -05:00
Kconfig net: netprio: rename config to be more consistent with cgroup configs 2014-01-03 23:41:42 +01:00
Makefile net: move 6lowpan compression code to separate module 2014-01-15 15:36:38 -08:00
nonet.c
socket.c net: handle error more gracefully in socketpair() 2013-12-10 22:24:13 -05:00
sysctl_net.c net: Update the sysctl permissions handler to test effective uid/gid 2013-10-07 15:57:56 -04:00