Wireless scanning while turning off the radio problem..

[Linus Torvalds <torvalds@linux-foundation.org>]

So there seems to be some issue with unlucky timing when turning off
wireless while the driver is busy scanning. I can't reproduce this, so
it's a one-off, but it's not just ugly warnings, the kernel woudln't
scan any wireless on that device afterwards and I had to reboot to get
networking back, so there is some long-term damage.

This is with Intel wireless (iwlwifi, it's a iwl N7260 thing, rev
0x144 if anybody cares) , but the warning callbacks don't seem to be
iwl-specific.

This was a recent top-of-git kernel (3.19.0-rc4-00241-gfc7f0dd38172 to
be exact).

Anybody have any ideas? Anything in particular I should try out to
help possibly get more information?

              Linus

---
[  204.361145] iwlwifi 0000:01:00.0: RF_KILL bit toggled to disable radio.
[  204.362358] ------------[ cut here ]------------
[  204.362383] WARNING: CPU: 0 PID: 37 at net/wireless/core.c:1011
cfg80211_netdev_notifier_call+0x491/0x500 [cfg80211]()
[  204.362385] Modules linked in: ccm rfcomm fuse ip6t_rpfilter
ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6
nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_nat
ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_mangle
ip6table_security ip6table_raw ip6table_filter ip6_tables
iptable_mangle iptable_security iptable_raw bnep arc4 vfat fat
x86_pkg_temp_thermal pn544_mei mei_phy pn544 coretemp hci kvm_intel
nfc iTCO_wdt iTCO_vendor_support kvm iwlmvm uvcvideo
snd_hda_codec_realtek microcode snd_hda_codec_generic
snd_hda_codec_hdmi mac80211 videobuf2_vmalloc videobuf2_memops
videobuf2_core v4l2_common snd_hda_intel videodev snd_hda_controller
joydev btusb media hid_multitouch i2c_i801 snd_hda_codec serio_raw
iwlwifi bluetooth snd_hwdep snd_seq cfg80211 snd_seq_device
[  204.362432]  snd_pcm sony_laptop rfkill mei_me snd_timer mei snd
lpc_ich mfd_core shpchp soundcore dm_crypt i915 crct10dif_pclmul
crc32_pclmul crc32c_intel i2c_algo_bit ghash_clmulni_intel
drm_kms_helper drm i2c_core video
[  204.362453] CPU: 0 PID: 37 Comm: kworker/0:1 Not tainted
3.19.0-rc4-00241-gfc7f0dd38172 #14
[  204.362455] Hardware name: Sony Corporation SVP11213CXB/VAIO, BIOS
R0270V7 05/17/2013
[  204.362464] Workqueue: events cfg80211_rfkill_sync_work [cfg80211]
[  204.362467]  0000000000000000 ffffffffc0375870 ffffffff815eb39a
0000000000000000
[  204.362471]  ffffffff8106c357 ffff8800d3b12890 ffff8800d9e08260
0000000000000002
[  204.362475]  ffff8800d3b12000 ffff8800d9e08000 ffffffffc0350161
ffff8800d365dc00
[  204.362479] Call Trace:
[  204.362490]  [<ffffffff815eb39a>] ? dump_stack+0x40/0x50
[  204.362496]  [<ffffffff8106c357>] ? warn_slowpath_common+0x77/0xb0
[  204.362506]  [<ffffffffc0350161>] ?
cfg80211_netdev_notifier_call+0x491/0x500 [cfg80211]
[  204.362513]  [<ffffffff814f3769>] ? __dev_remove_pack+0x39/0xa0
[  204.362538]  [<ffffffff815d9d0c>] ? __unregister_prot_hook+0xcc/0xd0
[  204.362542]  [<ffffffff815da89c>] ? packet_notifier+0x15c/0x1b0
[  204.362549]  [<ffffffff81086e65>] ? notifier_call_chain+0x45/0x70
[  204.362552]  [<ffffffff814f41a9>] ? dev_close_many+0xb9/0x110
[  204.362556]  [<ffffffff814f65da>] ? dev_close.part.87+0x2a/0x40
[  204.362559]  [<ffffffff814f6609>] ? dev_close+0x19/0x20
[  204.362569]  [<ffffffffc034f76d>] ?
cfg80211_shutdown_all_interfaces+0x3d/0xb0 [cfg80211]
[  204.362577]  [<ffffffffc034f809>] ?
cfg80211_rfkill_sync_work+0x29/0x30 [cfg80211]
[  204.362580]  [<ffffffff81081335>] ? process_one_work+0x135/0x370
[  204.362585]  [<ffffffff8107e927>] ? pwq_activate_delayed_work+0x27/0x40
[  204.362589]  [<ffffffff810818c3>] ? worker_thread+0x63/0x480
[  204.362592]  [<ffffffff81081860>] ? rescuer_thread+0x2f0/0x2f0
[  204.362596]  [<ffffffff8108606e>] ? kthread+0xce/0xf0
[  204.362600]  [<ffffffff81085fa0>] ? kthread_create_on_node+0x180/0x180
[  204.362605]  [<ffffffff815f0eac>] ? ret_from_fork+0x7c/0xb0
[  204.362609]  [<ffffffff81085fa0>] ? kthread_create_on_node+0x180/0x180
[  204.362612] ---[ end trace d0ac2826f7d2747f ]---

[  204.362614] ------------[ cut here ]------------
[  204.362628] WARNING: CPU: 0 PID: 37 at net/mac80211/driver-ops.h:12
ieee80211_request_sched_scan_stop+0xdd/0xf0 [mac80211]()
[  204.362630] wlp1s0:  Failed check-sdata-in-driver check, flags: 0x4
[  204.362631] Modules linked in: ccm rfcomm fuse ip6t_rpfilter
ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6
nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_nat
ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_mangle
ip6table_security ip6table_raw ip6table_filter ip6_tables
iptable_mangle iptable_security iptable_raw bnep arc4 vfat fat
x86_pkg_temp_thermal pn544_mei mei_phy pn544 coretemp hci kvm_intel
nfc iTCO_wdt iTCO_vendor_support kvm iwlmvm uvcvideo
snd_hda_codec_realtek microcode snd_hda_codec_generic
snd_hda_codec_hdmi mac80211 videobuf2_vmalloc videobuf2_memops
videobuf2_core v4l2_common snd_hda_intel videodev snd_hda_controller
joydev btusb media hid_multitouch i2c_i801 snd_hda_codec serio_raw
iwlwifi bluetooth snd_hwdep snd_seq cfg80211 snd_seq_device
[  204.362677]  snd_pcm sony_laptop rfkill mei_me snd_timer mei snd
lpc_ich mfd_core shpchp soundcore dm_crypt i915 crct10dif_pclmul
crc32_pclmul crc32c_intel i2c_algo_bit ghash_clmulni_intel
drm_kms_helper drm i2c_core video
[  204.362695] CPU: 0 PID: 37 Comm: kworker/0:1 Tainted: G        W
  3.19.0-rc4-00241-gfc7f0dd38172 #14
[  204.362697] Hardware name: Sony Corporation SVP11213CXB/VAIO, BIOS
R0270V7 05/17/2013
[  204.362703] Workqueue: events cfg80211_rfkill_sync_work [cfg80211]
[  204.362705]  0000000000000000 ffffffffc04e3491 ffffffff815eb39a
ffff88011a697c18
[  204.362709]  ffffffff8106c357 ffff8800d9e08660 ffff8800d3b12880
00000000fffffffb
[  204.362713]  ffff8800d9e09618 ffff8800d9e08000 ffffffff8106c3d5
ffffffffc04e0e78
[  204.362717] Call Trace:
[  204.362723]  [<ffffffff815eb39a>] ? dump_stack+0x40/0x50
[  204.362726]  [<ffffffff8106c357>] ? warn_slowpath_common+0x77/0xb0
[  204.362730]  [<ffffffff8106c3d5>] ? warn_slowpath_fmt+0x45/0x50
[  204.362743]  [<ffffffffc049374d>] ?
ieee80211_request_sched_scan_stop+0xdd/0xf0 [mac80211]
[  204.362755]  [<ffffffffc0357a33>] ?
__cfg80211_stop_sched_scan+0x73/0xb0 [cfg80211]
[  204.362763]  [<ffffffffc035016b>] ?
cfg80211_netdev_notifier_call+0x49b/0x500 [cfg80211]
[  204.362768]  [<ffffffff814f3769>] ? __dev_remove_pack+0x39/0xa0
[  204.362772]  [<ffffffff815d9d0c>] ? __unregister_prot_hook+0xcc/0xd0
[  204.362776]  [<ffffffff815da89c>] ? packet_notifier+0x15c/0x1b0
[  204.362781]  [<ffffffff81086e65>] ? notifier_call_chain+0x45/0x70
[  204.362785]  [<ffffffff814f41a9>] ? dev_close_many+0xb9/0x110
[  204.362788]  [<ffffffff814f65da>] ? dev_close.part.87+0x2a/0x40
[  204.362792]  [<ffffffff814f6609>] ? dev_close+0x19/0x20
[  204.362800]  [<ffffffffc034f76d>] ?
cfg80211_shutdown_all_interfaces+0x3d/0xb0 [cfg80211]
[  204.362807]  [<ffffffffc034f809>] ?
cfg80211_rfkill_sync_work+0x29/0x30 [cfg80211]
[  204.362811]  [<ffffffff81081335>] ? process_one_work+0x135/0x370
[  204.362815]  [<ffffffff8107e927>] ? pwq_activate_delayed_work+0x27/0x40
[  204.362819]  [<ffffffff810818c3>] ? worker_thread+0x63/0x480
[  204.362822]  [<ffffffff81081860>] ? rescuer_thread+0x2f0/0x2f0
[  204.362826]  [<ffffffff8108606e>] ? kthread+0xce/0xf0
[  204.362830]  [<ffffffff81085fa0>] ? kthread_create_on_node+0x180/0x180
[  204.362834]  [<ffffffff815f0eac>] ? ret_from_fork+0x7c/0xb0
[  204.362838]  [<ffffffff81085fa0>] ? kthread_create_on_node+0x180/0x180
[  204.362840] ---[ end trace d0ac2826f7d27480 ]---