linux/drivers
Emmanuel Grumbach 1c4abec0ba iwlwifi: mvm: fix setting channel in monitor mode
There was a deadlock in monitor mode when we were setting the
channel if the channel was not 1.

======================================================
[ INFO: possible circular locking dependency detected ]
3.14.3 #4 Not tainted
-------------------------------------------------------
iw/3323 is trying to acquire lock:
 (&local->chanctx_mtx){+.+.+.}, at: [<ffffffffa062e2f2>] ieee80211_vif_release_channel+0x42/0xb0 [mac80211]

but task is already holding lock:
 (&local->iflist_mtx){+.+...}, at: [<ffffffffa0609e0a>] ieee80211_set_monitor_channel+0x5a/0x1b0 [mac80211]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&local->iflist_mtx){+.+...}:
       [<ffffffff810d95bb>] __lock_acquire+0xb3b/0x13b0
       [<ffffffff810d9ee0>] lock_acquire+0xb0/0x1f0
       [<ffffffff817eb9c8>] mutex_lock_nested+0x78/0x4f0
       [<ffffffffa06225cf>] ieee80211_iterate_active_interfaces+0x2f/0x60 [mac80211]
       [<ffffffffa0518189>] iwl_mvm_recalc_multicast+0x49/0xa0 [iwlmvm]
       [<ffffffffa051822e>] iwl_mvm_configure_filter+0x4e/0x70 [iwlmvm]
       [<ffffffffa05e6d43>] ieee80211_configure_filter+0x153/0x5f0 [mac80211]
       [<ffffffffa05e71f5>] ieee80211_reconfig_filter+0x15/0x20 [mac80211]
       [snip]

-> #1 (&mvm->mutex){+.+.+.}:
       [<ffffffff810d95bb>] __lock_acquire+0xb3b/0x13b0
       [<ffffffff810d9ee0>] lock_acquire+0xb0/0x1f0
       [<ffffffff817eb9c8>] mutex_lock_nested+0x78/0x4f0
       [<ffffffffa0517246>] iwl_mvm_add_chanctx+0x56/0xe0 [iwlmvm]
       [<ffffffffa062ca1e>] ieee80211_new_chanctx+0x13e/0x410 [mac80211]
       [<ffffffffa062d953>] ieee80211_vif_use_channel+0x1c3/0x5a0 [mac80211]
       [<ffffffffa06035ab>] ieee80211_add_virtual_monitor+0x1ab/0x6b0 [mac80211]
       [<ffffffffa06052ea>] ieee80211_do_open+0xe6a/0x15a0 [mac80211]
       [<ffffffffa0605a79>] ieee80211_open+0x59/0x60 [mac80211]
       [snip]

-> #0 (&local->chanctx_mtx){+.+.+.}:
       [<ffffffff810d6cb7>] check_prevs_add+0x977/0x980
       [<ffffffff810d95bb>] __lock_acquire+0xb3b/0x13b0
       [<ffffffff810d9ee0>] lock_acquire+0xb0/0x1f0
       [<ffffffff817eb9c8>] mutex_lock_nested+0x78/0x4f0
       [<ffffffffa062e2f2>] ieee80211_vif_release_channel+0x42/0xb0 [mac80211]
       [<ffffffffa0609ec3>] ieee80211_set_monitor_channel+0x113/0x1b0 [mac80211]
       [<ffffffffa058fb37>] cfg80211_set_monitor_channel+0x77/0x2b0 [cfg80211]
       [<ffffffffa056e0b2>] __nl80211_set_channel+0x122/0x140 [cfg80211]
       [<ffffffffa0581374>] nl80211_set_wiphy+0x284/0xaf0 [cfg80211]
       [snip]

other info that might help us debug this:

Chain exists of:
  &local->chanctx_mtx --> &mvm->mutex --> &local->iflist_mtx

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&local->iflist_mtx);
                               lock(&mvm->mutex);
                               lock(&local->iflist_mtx);
  lock(&local->chanctx_mtx);

 *** DEADLOCK ***

This deadlock actually occurs:
INFO: task iw:3323 blocked for more than 120 seconds.
      Not tainted 3.14.3 #4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
iw              D ffff8800c8afcd80  4192  3323   3322 0x00000000
 ffff880078fdb7e0 0000000000000046 ffff8800c8afcd80 ffff880078fdbfd8
 00000000001d5540 00000000001d5540 ffff8801141b0000 ffff8800c8afcd80
 ffff880078ff9e38 ffff880078ff9e38 ffff880078ff9e40 0000000000000246
Call Trace:
 [<ffffffff817ea841>] schedule_preempt_disabled+0x31/0x80
 [<ffffffff817ebaed>] mutex_lock_nested+0x19d/0x4f0
 [<ffffffffa06225cf>] ? ieee80211_iterate_active_interfaces+0x2f/0x60 [mac80211]
 [<ffffffffa06225cf>] ? ieee80211_iterate_active_interfaces+0x2f/0x60 [mac80211]
 [<ffffffffa052a680>] ? iwl_mvm_power_mac_update_mode+0xc0/0xc0 [iwlmvm]
 [<ffffffffa06225cf>] ieee80211_iterate_active_interfaces+0x2f/0x60 [mac80211]
 [<ffffffffa0529357>] _iwl_mvm_power_update_binding+0x27/0x80 [iwlmvm]
 [<ffffffffa0516eb1>] iwl_mvm_unassign_vif_chanctx+0x81/0xc0 [iwlmvm]
 [<ffffffffa062d3ff>] __ieee80211_vif_release_channel+0xdf/0x470 [mac80211]
 [<ffffffffa062e2fa>] ieee80211_vif_release_channel+0x4a/0xb0 [mac80211]
 [<ffffffffa0609ec3>] ieee80211_set_monitor_channel+0x113/0x1b0 [mac80211]
 [<ffffffffa058fb37>] cfg80211_set_monitor_channel+0x77/0x2b0 [cfg80211]
 [<ffffffffa056e0b2>] __nl80211_set_channel+0x122/0x140 [cfg80211]
 [<ffffffffa0581374>] nl80211_set_wiphy+0x284/0xaf0 [cfg80211]

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=75541

Cc: <stable@vger.kernel.org> [3.13+]
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
2014-05-11 13:10:08 +03:00
..
accessibility
acpi Merge branches 'acpi-cleanup' and 'acpi-video' 2014-02-06 23:08:54 +01:00
amba
ata ACPI and power management updates for 3.14-rc1 2014-01-24 15:51:02 -08:00
atm
auxdisplay
base regmap: Updates for v3.14 2014-01-25 13:18:00 -08:00
bcma Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-01-30 17:20:32 -08:00
block Bug-fixes: 2014-02-05 16:01:11 -08:00
bluetooth Bluetooth: Fix endianess issue in the ath3k driver 2014-03-07 20:09:40 +02:00
bus drivers: bus: fix CCI driver kcalloc call parameters swap 2014-01-31 15:15:13 -08:00
cdrom Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-block 2014-01-30 11:40:10 -08:00
char fix a kmap leak in virtio_console 2014-02-09 15:21:16 -05:00
clk The second half of the clock framework pull requeust for 3.14 is 2014-01-28 18:44:53 -08:00
clocksource clocksource: kona: Add basic use of external clock 2014-01-31 21:04:01 -08:00
connector
cpufreq intel_pstate: Take core C0 time into account for core busy calculation 2014-02-04 21:41:15 +01:00
cpuidle powerpc/powernv/cpuidle: Back-end cpuidle driver for powernv platform. 2014-01-29 17:02:24 +11:00
crypto ARM: driver updates for 3.14 2014-01-23 18:49:36 -08:00
dca
devfreq Merge branches 'pm-cpufreq' and 'pm-devfreq' 2014-01-29 11:48:23 +01:00
dio
dma Merge branch 'for-linus' of git://git.infradead.org/users/vkoul/slave-dma 2014-01-29 20:27:23 -08:00
edac Merge branch 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-01-20 12:10:27 -08:00
eisa Revert "EISA: Initialize device before its resources" 2014-01-17 14:57:29 -07:00
extcon extcon: gpio: Add power resume support 2014-01-09 09:53:30 +09:00
firewire firewire: Enable remote DMA above 4 GB 2014-01-20 01:11:13 +01:00
firmware firmware/google: drop 'select EFI' to avoid recursive dependency 2014-01-27 21:02:40 -08:00
fmc
gpio ARM: driver updates for 3.14 2014-01-23 18:49:36 -08:00
gpu drm/radeon: allow geom rings to be setup on r600/r700 (v2) 2014-02-06 12:13:52 +10:00
hid Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2014-01-31 09:31:14 -08:00
hsi
hv hyperv: Add support for physically discontinuous receive buffer 2014-01-27 16:40:45 -08:00
hwmon hwmon: (da9055) Remove use of regmap_irq_get_virq() 2014-02-06 17:22:33 -08:00
hwspinlock
i2c Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2014-01-29 19:56:20 -08:00
ide drivers: ide: Include appropriate header file in ide-pio-blacklist.c 2014-01-28 23:35:09 -08:00
idle ACPI and power management updates for 3.14-rc1 2014-01-24 15:51:02 -08:00
iio Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2014-01-22 21:21:55 -08:00
infiniband Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-01-31 15:31:23 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2014-01-24 17:17:30 -08:00
iommu IOMMU Updates for Linux v3.14 2014-01-29 20:00:13 -08:00
ipack
irqchip Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-02-05 16:02:53 -08:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
leds Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/linux-leds 2014-01-28 18:53:01 -08:00
lguest
macintosh Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2014-01-27 21:11:26 -08:00
mailbox drivers/mailbox/omap: make mbox->irq signed for error handling 2014-01-23 16:36:53 -08:00
md Merge branch 'for-3.14/drivers' of git://git.kernel.dk/linux-block 2014-01-30 11:40:10 -08:00
media [media] adv7842: Composite free-run platfrom-data fix 2014-02-04 06:46:10 -02:00
memory
memstick drivers/memstick/host/rtsx_pci_ms.c: fix ms card data transfer bug 2014-01-23 16:37:04 -08:00
message Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block 2014-01-30 11:19:05 -08:00
mfd regulator: Updates for v3.14 2014-01-25 13:19:10 -08:00
misc Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging 2014-01-29 18:56:27 -08:00
mmc MMC highlights for 3.14: 2014-01-26 11:00:41 -08:00
mtd * Improve the NOR erasure quirk - now it tries to do as little writes as 2014-01-30 20:04:09 -08:00
net iwlwifi: mvm: fix setting channel in monitor mode 2014-05-11 13:10:08 +03:00
nfc NFC: trf7970a: Add ISO/IEC 15693 and Type 5 tag Support 2014-03-11 00:47:09 +01:00
ntb
nubus
of Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
oprofile
parisc
parport TTY/Serial driver patches for 3.14-rc1 2014-01-20 16:05:23 -08:00
pci ACPI / hotplug / PCI: Fix bridge removal race vs dock events 2014-02-03 22:30:15 +01:00
pcmcia PCI changes for the v3.14 merge window: 2014-01-22 16:39:28 -08:00
phy Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
pinctrl pinctrl: tegra: return correct error type 2014-02-06 14:21:19 +01:00
platform platform/chrome: Cleanups and improvements 2014-01-29 20:06:01 -08:00
pnp Merge branch 'pnp' 2014-01-12 23:48:18 +01:00
power Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
powercap
pps
ps3
ptp ptp_pch: Add dependency on HAS_IOMEM 2014-01-15 14:51:22 -08:00
pwm pwm: Changes for v3.14-rc1 2014-01-27 08:15:51 -08:00
rapidio
regulator Merge remote-tracking branches 'regulator/fix/ab3100' and 'regulator/fix/s2mps11' into regulator-linus 2014-02-04 12:58:19 +00:00
remoteproc
reset
rpmsg
rtc Merge branch 'akpm' (incoming from Andrew) 2014-01-23 19:11:50 -08:00
s390 Second batch of KVM updates. Some minor x86 fixes, 2014-01-31 08:37:32 -08:00
sbus sparc: delete non-required instances of include <linux/init.h> 2014-01-28 23:38:23 -08:00
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-01-31 15:31:23 -08:00
sfi
sh
sn
spi Merge remote-tracking branch 'agust/next' into next 2014-01-29 16:53:55 +11:00
ssb Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-01-30 17:20:32 -08:00
staging wlan-ng: fixup staging driver for removal of ieee80211_dsss_chan_to_freq 2014-03-13 14:05:39 -04:00
target Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-01-31 15:31:23 -08:00
tc
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2014-01-24 17:13:49 -08:00
tty Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-01-30 17:20:32 -08:00
uio
usb Merge remote-tracking branch 'agust/next' into next 2014-01-29 16:53:55 +11:00
uwb
vfio Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2014-01-27 21:11:26 -08:00
vhost Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2014-01-31 15:31:23 -08:00
video parisc/sti_console: prefer Linux fonts over built-in ROM fonts 2014-02-02 20:56:47 +01:00
virt
virtio A few simple fixes. Quiet cycle. 2014-01-22 22:24:35 -08:00
vlynq drivers/vlynq/vlynq.c: fix another resource size off by 1 error 2014-01-23 16:36:55 -08:00
vme
w1 drivers/w1/masters/w1-gpio.c: add strong pullup emulation 2014-01-23 16:37:04 -08:00
watchdog watchdog: dw_wdt: Add dependency on HAS_IOMEM 2014-02-08 09:47:11 +01:00
xen Bug-fixes: 2014-02-05 16:01:11 -08:00
zorro
Kconfig
Makefile