linux-stable.git/drivers/net/wireless, branch v3.2.22 Linux kernel stable tree iwlwifi: remove log_event debugfs file debugging is disabled 2012-07-04T04:44:23+00:00 Johannes Berg johannes.berg@intel.com 2012-06-20T06:46:25+00:00 468267529e13b35307410c8e7bd09bc41d063c79 commit 882b7b7d11d65e8eccce738f1ce97cdfdb998f9f upstream. When debugging is disabled, the event log functions aren't functional in the way that the debugfs file expects. This leads to the debugfs access crashing. Since the event log functions aren't functional then, remove the debugfs file when CONFIG_IWLWIFI_DEBUG is not set. Reported-by: Lekensteyn <lekensteyn@gmail.com> Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 882b7b7d11d65e8eccce738f1ce97cdfdb998f9f upstream.

When debugging is disabled, the event log functions aren't
functional in the way that the debugfs file expects. This
leads to the debugfs access crashing. Since the event log
functions aren't functional then, remove the debugfs file
when CONFIG_IWLWIFI_DEBUG is not set.

Reported-by: Lekensteyn <lekensteyn@gmail.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k_hw: avoid possible infinite loop in ar9003_get_pll_sqsum_dvc 2012-07-04T04:44:23+00:00 Mohammed Shafi Shajakhan mohammed@qca.qualcomm.com 2012-06-18T07:43:30+00:00 8ec8fdb5e62e6a7ff9956217b32dae6bc46328ec commit f18e3c6b67f448ec47b3a5b242789bd3d5644879 upstream. "ath9k: Fix softlockup in AR9485" with commit id 64bc1239c790e051ff677e023435d770d2ffa174 fixed the reported issue, yet its better to avoid the possible infinite loop in ar9003_get_pll_sqsum_dvc by having a timeout as suggested by ath9k maintainers. http://www.spinics.net/lists/linux-wireless/msg92126.html. Based on my testing PLL's locking measurement is done in ~200us (2 iterations). Cc: Rolf Offermanns <rolf.offermanns@gmx.net> Cc: Sujith Manoharan <c_manoha@qca.qualcomm.com> Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit f18e3c6b67f448ec47b3a5b242789bd3d5644879 upstream.

"ath9k: Fix softlockup in AR9485" with commit id
64bc1239c790e051ff677e023435d770d2ffa174 fixed the reported
issue, yet its better to avoid the possible infinite loop
in ar9003_get_pll_sqsum_dvc by having a timeout as suggested
by ath9k maintainers.
http://www.spinics.net/lists/linux-wireless/msg92126.html.
Based on my testing PLL's locking measurement is done in
~200us (2 iterations).

Cc: Rolf Offermanns <rolf.offermanns@gmx.net>
Cc: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Cc: Senthil Balasubramanian <senthilb@qca.qualcomm.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k: fix a tx rate duration calculation bug 2012-07-04T04:44:21+00:00 Felix Fietkau nbd@openwrt.org 2012-06-15T01:04:52+00:00 4c42ad8fcf33fee7b949a6355b71a773843131b9 commit 76591bea9714a58d8924154068c78d702eb2cb17 upstream. The rate pointer variable for a rate series is used in a loop before it is initialized. This went unnoticed because it was used earlier for the RTS/CTS rate. This bug can lead to the wrong PHY type being passed to the duration calculation function. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 76591bea9714a58d8924154068c78d702eb2cb17 upstream.

The rate pointer variable for a rate series is used in a loop before it is
initialized. This went unnoticed because it was used earlier for the RTS/CTS
rate. This bug can lead to the wrong PHY type being passed to the
duration calculation function.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k: Fix softlockup in AR9485 2012-07-04T04:44:19+00:00 Mohammed Shafi Shajakhan mohammed@qca.qualcomm.com 2012-06-13T15:58:09+00:00 bc623ac31d51f12113e40085f08fbccf585220bd commit bcb7ad7bcbef030e6ba71ede1f9866368aca7c99 upstream. steps to recreate: load latest ath9k driver with AR9485 stop the network-manager and wpa_supplicant bring the interface up Call Trace: [<ffffffffa0517490>] ? ath_hw_check+0xe0/0xe0 [ath9k] [<ffffffff812cd1e8>] __const_udelay+0x28/0x30 [<ffffffffa03bae7a>] ar9003_get_pll_sqsum_dvc+0x4a/0x80 [ath9k_hw] [<ffffffffa05174eb>] ath_hw_pll_work+0x5b/0xe0 [ath9k] [<ffffffff810744fe>] process_one_work+0x11e/0x470 [<ffffffff8107530f>] worker_thread+0x15f/0x360 [<ffffffff810751b0>] ? manage_workers+0x230/0x230 [<ffffffff81079af3>] kthread+0x93/0xa0 [<ffffffff815fd3a4>] kernel_thread_helper+0x4/0x10 [<ffffffff81079a60>] ? kthread_freezable_should_stop+0x70/0x70 [<ffffffff815fd3a0>] ? gs_change+0x13/0x13 ensure that the PLL-WAR for AR9485/AR9340 is executed only if the STA is associated (or) IBSS/AP mode had started beaconing. Ideally this WAR is needed to recover from some rare beacon stuck during stress testing. Before the STA is associated/IBSS had started beaconing, PLL4(0x1618c) always seem to have zero even though we had configured PLL3(0x16188) to query about PLL's locking status. When we keep on polling infinitely PLL4's 8th bit(ie check for PLL locking measurements is done), machine hangs due to softlockup. fixes https://bugzilla.redhat.com/show_bug.cgi?id=811142 Reported-by: Rolf Offermanns <rolf.offermanns@gmx.net> Tested-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit bcb7ad7bcbef030e6ba71ede1f9866368aca7c99 upstream.

steps to recreate:
load latest ath9k driver with AR9485
stop the network-manager and wpa_supplicant
bring the interface up

	Call Trace:
	[<ffffffffa0517490>] ? ath_hw_check+0xe0/0xe0 [ath9k]
	[<ffffffff812cd1e8>] __const_udelay+0x28/0x30
	[<ffffffffa03bae7a>] ar9003_get_pll_sqsum_dvc+0x4a/0x80 [ath9k_hw]
	[<ffffffffa05174eb>] ath_hw_pll_work+0x5b/0xe0 [ath9k]
	[<ffffffff810744fe>] process_one_work+0x11e/0x470
	[<ffffffff8107530f>] worker_thread+0x15f/0x360
	[<ffffffff810751b0>] ? manage_workers+0x230/0x230
	[<ffffffff81079af3>] kthread+0x93/0xa0
	[<ffffffff815fd3a4>] kernel_thread_helper+0x4/0x10
	[<ffffffff81079a60>] ? kthread_freezable_should_stop+0x70/0x70
	[<ffffffff815fd3a0>] ? gs_change+0x13/0x13

ensure that the PLL-WAR for AR9485/AR9340 is executed only if the STA is
associated (or) IBSS/AP mode had started beaconing. Ideally this WAR
is needed to recover from some rare beacon stuck during stress testing.
Before the STA is associated/IBSS had started beaconing, PLL4(0x1618c)
always seem to have zero even though we had configured PLL3(0x16188) to
query about PLL's locking status. When we keep on polling infinitely PLL4's
8th bit(ie check for PLL locking measurements is done), machine hangs
due to softlockup.

fixes https://bugzilla.redhat.com/show_bug.cgi?id=811142

Reported-by: Rolf Offermanns <rolf.offermanns@gmx.net>
Tested-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ath9k: Fix a WARNING on suspend/resume with IBSS 2012-07-04T04:44:18+00:00 Mohammed Shafi Shajakhan mohammed@qca.qualcomm.com 2012-06-06T05:03:10+00:00 14dd08df3f117f3e9b70552fb68b2d3660f5c2e7 commit 2031b4c2b4904f7448ab9e4bc6b9bf16e32709f5 upstream. this patch is dependent on the patch "cfg80211: fix interface combinations" In ath9k currently we have ADHOC interface as a single incompatible interface. when drv_add_interface is called during resume we got to consider number of vifs already present in addition to checking the drivers 'opmode' information about ADHOC. we incorrectly assume an ADHOC interface is already present. Then we may miss some driver specific data for the ADHOC interface after resume. The above mentioned checks can be removed from the driver, as the patch 'cfg80211: fix interface combinations' ensures that if an interface type is not advertised by the driver in any of the interface combinations(via ieee80211_iface_combination) then it shall be treated as a single incompatible interface. Fixes the following warning on suspend/resume with ibss interface. ath: phy0: Cannot create ADHOC interface when other interfaces already exist. WARNING: at net/mac80211/driver-ops.h:12 ieee80211_reconfig+0x1882/0x1ca0 [mac80211]() Hardware name: 2842RK1 wlan2: Failed check-sdata-in-driver check, flags: 0x0 Call Trace: [<c01361b2>] warn_slowpath_common+0x72/0xa0 [<f8aaa7c2>] ? ieee80211_reconfig+0x1882/0x1ca0 [mac80211] [<f8aaa7c2>] ? ieee80211_reconfig+0x1882/0x1ca0 [mac80211] [<c0136283>] warn_slowpath_fmt+0x33/0x40 [<f8aaa7c2>] ieee80211_reconfig+0x1882/0x1ca0 [mac80211] [<c06c1d1a>] ? mutex_lock_nested+0x23a/0x2f0 [<f8a95097>] ieee80211_resume+0x27/0x70 [mac80211] [<fd177edf>] wiphy_resume+0x8f/0xa0 [cfg80211] Cc: Rajkumar Manoharan <rmanohar@qca.qualcomm.com> Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 2031b4c2b4904f7448ab9e4bc6b9bf16e32709f5 upstream.

this patch is dependent on the patch "cfg80211: fix interface
combinations"

In ath9k currently we have ADHOC interface as a single incompatible
interface. when drv_add_interface is called during resume we got to
consider number of vifs already present in addition to checking the
drivers 'opmode' information about ADHOC.  we incorrectly assume
an ADHOC interface is already present. Then we may miss some driver
specific data for the ADHOC interface after resume.

The above mentioned checks can be removed from the driver,
as the patch 'cfg80211: fix interface combinations' ensures that
if an interface type is not advertised by the driver in any of the
interface combinations(via ieee80211_iface_combination) then it shall
be treated as a single incompatible interface. Fixes the following
warning on suspend/resume with ibss interface.

        ath: phy0: Cannot create ADHOC interface when other
        interfaces already exist.
        WARNING: at net/mac80211/driver-ops.h:12
        ieee80211_reconfig+0x1882/0x1ca0 [mac80211]()
        Hardware name: 2842RK1
        wlan2:  Failed check-sdata-in-driver check, flags: 0x0

        Call Trace:
        [<c01361b2>] warn_slowpath_common+0x72/0xa0
        [<f8aaa7c2>] ? ieee80211_reconfig+0x1882/0x1ca0
        [mac80211]
        [<f8aaa7c2>] ? ieee80211_reconfig+0x1882/0x1ca0
        [mac80211]
        [<c0136283>] warn_slowpath_fmt+0x33/0x40
        [<f8aaa7c2>] ieee80211_reconfig+0x1882/0x1ca0 [mac80211]
        [<c06c1d1a>] ? mutex_lock_nested+0x23a/0x2f0
        [<f8a95097>] ieee80211_resume+0x27/0x70 [mac80211]
        [<fd177edf>] wiphy_resume+0x8f/0xa0 [cfg80211]

Cc: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
iwlwifi: disable the buggy chain extension feature in HW 2012-06-19T22:18:17+00:00 Emmanuel Grumbach emmanuel.grumbach@intel.com 2012-06-06T11:55:02+00:00 cbb05493366d341a1b66b2bf7488b4957ffc7e75 commit d012d04e4d6312ea157b6cf19e9689af934f5aa7 upstream. This feature has been reported to be buggy and enabled by default. We therefore need to disable it manually. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2 as instructed: pass bus(trans) to iwl_write_prph()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit d012d04e4d6312ea157b6cf19e9689af934f5aa7 upstream.

This feature has been reported to be buggy and enabled by
default. We therefore need to disable it manually.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2 as instructed: pass bus(trans) to iwl_write_prph()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
iwlwifi: use correct supported firmware for 6035 and 6000g2 2012-06-19T22:18:17+00:00 Meenakshi Venkataraman meenakshi.venkataraman@intel.com 2012-06-05T18:24:37+00:00 9e8ed57850a9d5157430fb09161a2456171d8684 commit d2c8b15d0cb486f4938ba7f2af349d9d1220cb10 upstream. My patch iwlwifi: use correct released ucode version did not correctly report supported firmware for the 6035 device. This patch fixes it. The minimum supported firmware version for 6035 is v6. Also correct the minimum supported firmware version for the 6000g2 series of devices. Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com> Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: - adjust context - make IWL_DEVICE_6035 identical for IWL_DEVICE_6030 except for the ucode_api_* fields] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit d2c8b15d0cb486f4938ba7f2af349d9d1220cb10 upstream.

My patch

   iwlwifi: use correct released ucode version

did not correctly report supported firmware
for the 6035 device. This patch fixes it. The
minimum supported firmware version for 6035
is v6.

Also correct the minimum supported firmware
version for the 6000g2 series of devices.

Signed-off-by: Meenakshi Venkataraman <meenakshi.venkataraman@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2:
 - adjust context
 - make IWL_DEVICE_6035 identical for IWL_DEVICE_6030 except for the
   ucode_api_* fields]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
iwlwifi: unregister LEDs if mac80211 registration fails 2012-06-19T22:18:13+00:00 Johannes Berg johannes.berg@intel.com 2012-06-05T07:38:35+00:00 ec2f2d36fb217a8750e4c82f91406f265174462f commit 0e1fa7ef25004b9c1a14147bce61c15c2f1c6744 upstream. Otherwise the LEDs stick around and cause issues the next time around since they're still there but not really hooked up. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit 0e1fa7ef25004b9c1a14147bce61c15c2f1c6744 upstream.

Otherwise the LEDs stick around and cause issues the
next time around since they're still there but not
really hooked up.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
iwlwifi: disable WoWLAN if !CONFIG_PM_SLEEP 2012-06-19T22:18:12+00:00 Johannes Berg johannes.berg@intel.com 2012-06-04T11:43:11+00:00 adf49ce365294f2b4cba66ea216be4470d77c792 commit fcb6ff5e2cb83e1de10631f6621f45ca3401bf61 upstream. If CONFIG_PM_SLEEP is disabled, then iwlwifi doesn't support suspend/resume handlers and thus mac80211 (correctly) refuses advertising WoWLAN. Disable WoWLAN in the driver in this case. Reported-by: Sebastian Kemper <sebastian_ml@gmx.net> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit fcb6ff5e2cb83e1de10631f6621f45ca3401bf61 upstream.

If CONFIG_PM_SLEEP is disabled, then iwlwifi doesn't
support suspend/resume handlers and thus mac80211
(correctly) refuses advertising WoWLAN. Disable
WoWLAN in the driver in this case.

Reported-by: Sebastian Kemper <sebastian_ml@gmx.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
[bwh: Backported to 3.2: adjust filename, context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
rt2x00: use atomic variable for seqno 2012-06-19T22:18:12+00:00 Stanislaw Gruszka sgruszka@redhat.com 2012-06-01T09:29:40+00:00 6c6967906305e4681c555338d8ad8823e8487c42 commit e5851dac2c95af7159716832300b9f50c62c648e upstream. Remove spinlock as atomic_t can be used instead. Note we use only 16 lower bits, upper bits are changed but we impilcilty cast to u16. This fix possible deadlock on IBSS mode reproted by lockdep: ================================= [ INFO: inconsistent lock state ] 3.4.0-wl+ #4 Not tainted --------------------------------- inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage. kworker/u:2/30374 [HC0[0]:SC0[0]:HE1:SE1] takes: (&(&intf->seqlock)->rlock){+.?...}, at: [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib] {IN-SOFTIRQ-W} state was registered at: [<c04978ab>] __lock_acquire+0x47b/0x1050 [<c0498504>] lock_acquire+0x84/0xf0 [<c0835733>] _raw_spin_lock+0x33/0x40 [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib] [<f9979f2a>] rt2x00queue_write_tx_frame+0x1a/0x300 [rt2x00lib] [<f997834f>] rt2x00mac_tx+0x7f/0x380 [rt2x00lib] [<f98fe363>] __ieee80211_tx+0x1b3/0x300 [mac80211] [<f98ffdf5>] ieee80211_tx+0x105/0x130 [mac80211] [<f99000dd>] ieee80211_xmit+0xad/0x100 [mac80211] [<f9900519>] ieee80211_subif_start_xmit+0x2d9/0x930 [mac80211] [<c0782e87>] dev_hard_start_xmit+0x307/0x660 [<c079bb71>] sch_direct_xmit+0xa1/0x1e0 [<c0784bb3>] dev_queue_xmit+0x183/0x730 [<c078c27a>] neigh_resolve_output+0xfa/0x1e0 [<c07b436a>] ip_finish_output+0x24a/0x460 [<c07b4897>] ip_output+0xb7/0x100 [<c07b2d60>] ip_local_out+0x20/0x60 [<c07e01ff>] igmpv3_sendpack+0x4f/0x60 [<c07e108f>] igmp_ifc_timer_expire+0x29f/0x330 [<c04520fc>] run_timer_softirq+0x15c/0x2f0 [<c0449e3e>] __do_softirq+0xae/0x1e0 irq event stamp: 18380437 hardirqs last enabled at (18380437): [<c0526027>] __slab_alloc.clone.3+0x67/0x5f0 hardirqs last disabled at (18380436): [<c0525ff3>] __slab_alloc.clone.3+0x33/0x5f0 softirqs last enabled at (18377616): [<c0449eb3>] __do_softirq+0x123/0x1e0 softirqs last disabled at (18377611): [<c041278d>] do_softirq+0x9d/0xe0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&(&intf->seqlock)->rlock); <Interrupt> lock(&(&intf->seqlock)->rlock); *** DEADLOCK *** 4 locks held by kworker/u:2/30374: #0: (wiphy_name(local->hw.wiphy)){++++.+}, at: [<c045cf99>] process_one_work+0x109/0x3f0 #1: ((&sdata->work)){+.+.+.}, at: [<c045cf99>] process_one_work+0x109/0x3f0 #2: (&ifibss->mtx){+.+.+.}, at: [<f98f005b>] ieee80211_ibss_work+0x1b/0x470 [mac80211] #3: (&intf->beacon_skb_mutex){+.+...}, at: [<f997a644>] rt2x00queue_update_beacon+0x24/0x50 [rt2x00lib] stack backtrace: Pid: 30374, comm: kworker/u:2 Not tainted 3.4.0-wl+ #4 Call Trace: [<c04962a6>] print_usage_bug+0x1f6/0x220 [<c0496a12>] mark_lock+0x2c2/0x300 [<c0495ff0>] ? check_usage_forwards+0xc0/0xc0 [<c04978ec>] __lock_acquire+0x4bc/0x1050 [<c0527890>] ? __kmalloc_track_caller+0x1c0/0x1d0 [<c0777fb6>] ? copy_skb_header+0x26/0x90 [<c0498504>] lock_acquire+0x84/0xf0 [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib] [<c0835733>] _raw_spin_lock+0x33/0x40 [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib] [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib] [<f997a5cf>] rt2x00queue_update_beacon_locked+0x5f/0xb0 [rt2x00lib] [<f997a64d>] rt2x00queue_update_beacon+0x2d/0x50 [rt2x00lib] [<f9977e3a>] rt2x00mac_bss_info_changed+0x1ca/0x200 [rt2x00lib] [<f9977c70>] ? rt2x00mac_remove_interface+0x70/0x70 [rt2x00lib] [<f98e4dd0>] ieee80211_bss_info_change_notify+0xe0/0x1d0 [mac80211] [<f98ef7b8>] __ieee80211_sta_join_ibss+0x3b8/0x610 [mac80211] [<c0496ab4>] ? mark_held_locks+0x64/0xc0 [<c0440012>] ? virt_efi_query_capsule_caps+0x12/0x50 [<f98efb09>] ieee80211_sta_join_ibss+0xf9/0x140 [mac80211] [<f98f0456>] ieee80211_ibss_work+0x416/0x470 [mac80211] [<c0496d8b>] ? trace_hardirqs_on+0xb/0x10 [<c077683b>] ? skb_dequeue+0x4b/0x70 [<f98f207f>] ieee80211_iface_work+0x13f/0x230 [mac80211] [<c045cf99>] ? process_one_work+0x109/0x3f0 [<c045d015>] process_one_work+0x185/0x3f0 [<c045cf99>] ? process_one_work+0x109/0x3f0 [<f98f1f40>] ? ieee80211_teardown_sdata+0xa0/0xa0 [mac80211] [<c045ed86>] worker_thread+0x116/0x270 [<c045ec70>] ? manage_workers+0x1e0/0x1e0 [<c0462f64>] kthread+0x84/0x90 [<c0462ee0>] ? __init_kthread_worker+0x60/0x60 [<c083d382>] kernel_thread_helper+0x6/0x10 Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Helmut Schaa <helmut.schaa@googlemail.com> Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk> 
commit e5851dac2c95af7159716832300b9f50c62c648e upstream.

Remove spinlock as atomic_t can be used instead. Note we use only 16
lower bits, upper bits are changed but we impilcilty cast to u16.

This fix possible deadlock on IBSS mode reproted by lockdep:

=================================
[ INFO: inconsistent lock state ]
3.4.0-wl+ #4 Not tainted
---------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
kworker/u:2/30374 [HC0[0]:SC0[0]:HE1:SE1] takes:
 (&(&intf->seqlock)->rlock){+.?...}, at: [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
{IN-SOFTIRQ-W} state was registered at:
  [<c04978ab>] __lock_acquire+0x47b/0x1050
  [<c0498504>] lock_acquire+0x84/0xf0
  [<c0835733>] _raw_spin_lock+0x33/0x40
  [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
  [<f9979f2a>] rt2x00queue_write_tx_frame+0x1a/0x300 [rt2x00lib]
  [<f997834f>] rt2x00mac_tx+0x7f/0x380 [rt2x00lib]
  [<f98fe363>] __ieee80211_tx+0x1b3/0x300 [mac80211]
  [<f98ffdf5>] ieee80211_tx+0x105/0x130 [mac80211]
  [<f99000dd>] ieee80211_xmit+0xad/0x100 [mac80211]
  [<f9900519>] ieee80211_subif_start_xmit+0x2d9/0x930 [mac80211]
  [<c0782e87>] dev_hard_start_xmit+0x307/0x660
  [<c079bb71>] sch_direct_xmit+0xa1/0x1e0
  [<c0784bb3>] dev_queue_xmit+0x183/0x730
  [<c078c27a>] neigh_resolve_output+0xfa/0x1e0
  [<c07b436a>] ip_finish_output+0x24a/0x460
  [<c07b4897>] ip_output+0xb7/0x100
  [<c07b2d60>] ip_local_out+0x20/0x60
  [<c07e01ff>] igmpv3_sendpack+0x4f/0x60
  [<c07e108f>] igmp_ifc_timer_expire+0x29f/0x330
  [<c04520fc>] run_timer_softirq+0x15c/0x2f0
  [<c0449e3e>] __do_softirq+0xae/0x1e0
irq event stamp: 18380437
hardirqs last  enabled at (18380437): [<c0526027>] __slab_alloc.clone.3+0x67/0x5f0
hardirqs last disabled at (18380436): [<c0525ff3>] __slab_alloc.clone.3+0x33/0x5f0
softirqs last  enabled at (18377616): [<c0449eb3>] __do_softirq+0x123/0x1e0
softirqs last disabled at (18377611): [<c041278d>] do_softirq+0x9d/0xe0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&intf->seqlock)->rlock);
  <Interrupt>
    lock(&(&intf->seqlock)->rlock);

 *** DEADLOCK ***

4 locks held by kworker/u:2/30374:
 #0:  (wiphy_name(local->hw.wiphy)){++++.+}, at: [<c045cf99>] process_one_work+0x109/0x3f0
 #1:  ((&sdata->work)){+.+.+.}, at: [<c045cf99>] process_one_work+0x109/0x3f0
 #2:  (&ifibss->mtx){+.+.+.}, at: [<f98f005b>] ieee80211_ibss_work+0x1b/0x470 [mac80211]
 #3:  (&intf->beacon_skb_mutex){+.+...}, at: [<f997a644>] rt2x00queue_update_beacon+0x24/0x50 [rt2x00lib]

stack backtrace:
Pid: 30374, comm: kworker/u:2 Not tainted 3.4.0-wl+ #4
Call Trace:
 [<c04962a6>] print_usage_bug+0x1f6/0x220
 [<c0496a12>] mark_lock+0x2c2/0x300
 [<c0495ff0>] ? check_usage_forwards+0xc0/0xc0
 [<c04978ec>] __lock_acquire+0x4bc/0x1050
 [<c0527890>] ? __kmalloc_track_caller+0x1c0/0x1d0
 [<c0777fb6>] ? copy_skb_header+0x26/0x90
 [<c0498504>] lock_acquire+0x84/0xf0
 [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
 [<c0835733>] _raw_spin_lock+0x33/0x40
 [<f9979a20>] ? rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
 [<f9979a20>] rt2x00queue_create_tx_descriptor+0x380/0x490 [rt2x00lib]
 [<f997a5cf>] rt2x00queue_update_beacon_locked+0x5f/0xb0 [rt2x00lib]
 [<f997a64d>] rt2x00queue_update_beacon+0x2d/0x50 [rt2x00lib]
 [<f9977e3a>] rt2x00mac_bss_info_changed+0x1ca/0x200 [rt2x00lib]
 [<f9977c70>] ? rt2x00mac_remove_interface+0x70/0x70 [rt2x00lib]
 [<f98e4dd0>] ieee80211_bss_info_change_notify+0xe0/0x1d0 [mac80211]
 [<f98ef7b8>] __ieee80211_sta_join_ibss+0x3b8/0x610 [mac80211]
 [<c0496ab4>] ? mark_held_locks+0x64/0xc0
 [<c0440012>] ? virt_efi_query_capsule_caps+0x12/0x50
 [<f98efb09>] ieee80211_sta_join_ibss+0xf9/0x140 [mac80211]
 [<f98f0456>] ieee80211_ibss_work+0x416/0x470 [mac80211]
 [<c0496d8b>] ? trace_hardirqs_on+0xb/0x10
 [<c077683b>] ? skb_dequeue+0x4b/0x70
 [<f98f207f>] ieee80211_iface_work+0x13f/0x230 [mac80211]
 [<c045cf99>] ? process_one_work+0x109/0x3f0
 [<c045d015>] process_one_work+0x185/0x3f0
 [<c045cf99>] ? process_one_work+0x109/0x3f0
 [<f98f1f40>] ? ieee80211_teardown_sdata+0xa0/0xa0 [mac80211]
 [<c045ed86>] worker_thread+0x116/0x270
 [<c045ec70>] ? manage_workers+0x1e0/0x1e0
 [<c0462f64>] kthread+0x84/0x90
 [<c0462ee0>] ? __init_kthread_worker+0x60/0x60
 [<c083d382>] kernel_thread_helper+0x6/0x10

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>