This reverts commit e6c5fc53.

Based on this regression report:

Date: Thu, 05 Nov 2009 15:59:16 +0100
From: Holger Schurig <holgerschurig@gmail.com>
To: linux-wireless@vger.kernel.org
Subject: BUG: oops when "rmmod ipw2200"

This happened on wireless-testing v2.6.32-rc6-41575-g5e68bfb. I
modprobed ipw2200, put it into monitor mode, used tshark a while to
monitor, then I stopped tshark, "ifconfig eth2 down" and finally
"rmmod ipw2200", and voila:

[  917.189620] ------------[ cut here ]------------
[  917.189717] kernel BUG at net/wireless/core.c:543!
[  917.189805] invalid opcode: 0000 [#1

] PREEMPT SMP
[  917.190002] last sysfs file: /sys/devices/pci0000:00/0000:00:1e.0/0000:02:0d.0/firmware/0000:02:0d.0/loading
[  917.190136] Modules linked in: lib80211_crypt_wep ipw2200(-) libipw lib80211 ath5k mac80211 ath cfg80211 psmouse uhci_hcd
[  917.190680]
[  917.190759] Pid: 1763, comm: rmmod Not tainted (2.6.32-rc6-wl #26) Amilo M1425
[  917.190886] EIP: 0060:[<f8accf34>] EFLAGS: 00010202 CPU: 0
[  917.190992] EIP is at wiphy_unregister+0xd3/0x175 [cfg80211]
[  917.191083] EAX: f601d4c4 EBX: 00000000 ECX: 00000000 EDX: f79e8600
[  917.191176] ESI: f601d400 EDI: f95b4350 EBP: f6009eb4 ESP: f6009e8c
[  917.191269]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[  917.191360] Process rmmod (pid: 1763, ti=f6008000 task=f79e8130 task.ti=f6008000)
[  917.191486] Stack:
[  917.191562]  f601d5a0 f601d484 f6460e98 f6009ea0 c01407ee f6009eb8 00000246 f64604c0
[  917.191916] <0> f6460e5c f95b4350 f6009ec0 f94fd030 f6460e98 f6009edc f95a9d4f f787bc00
[  917.192100] <0> f787bc58 f787bc00 f95b4350 f95b4350 f6009ee8 c0207fca f787bc58 f6009ef8
[  917.192100] Call Trace:
[  917.192100]  [<c01407ee>] ? trace_hardirqs_on+0xb/0xd
[  917.192100]  [<f94fd030>] ? unregister_ieee80211+0xe/0x27 [libipw]
[  917.192100]  [<f95a9d4f>] ? ipw_pci_remove+0x59/0x227 [ipw2200]
[  917.192100]  [<c0207fca>] ? pci_device_remove+0x19/0x39
[  917.192100]  [<c02b93a4>] ? __device_release_driver+0x59/0x9d
[  917.192100]  [<c02b944f>] ? driver_detach+0x67/0x85
[  917.192100]  [<c02b88d6>] ? bus_remove_driver+0x69/0x85
[  917.192100]  [<c02b9878>] ? driver_unregister+0x4d/0x54
[  917.192100]  [<c02081c3>] ? pci_unregister_driver+0x28/0x71
[  917.192100]  [<f95a9cf4>] ? ipw_exit+0x1c/0x1e [ipw2200]
[  917.192100]  [<c0148e2b>] ? sys_delete_module+0x192/0x1ef
[  917.192100]  [<c0162cdb>] ? remove_vma+0x52/0x58
[  917.192100]  [<c01028bb>] ? sysenter_exit+0xf/0x18
[  917.192100]  [<c0102888>] ? sysenter_do_call+0x12/0x36
[  917.192100] Code: 74 07 e8 81 bc 8c c7 eb c8 8d 55 e0 89 f8 e8 d6 6d 66 c7 8b 45 dc 31 d2 e8 81 cc 8c c7 8d 86 c4 00 00 00 39 86 c4 00 00 00 74 04 <0f> 0b eb fe 8b 45 dc 8d 5e 0c e8 5a cc 8c c7 8b 86 94 03 00 00
[  917.192100] EIP: [<f8accf34>] wiphy_unregister+0xd3/0x175 [cfg80211] SS:ESP 0068:f6009e8c
[  917.203718] ---[ end trace bcaaf449945a5100 ]---

Signed-off-by: John W. Linville <linville@tuxdriver.com>