[562980.584373] BUG: unable to handle kernel NULL pointer dereference at 000004a0
[562980.584384] IP: [<c0122c38>] __ticket_spin_lock+0x8/0x20
[562980.584396] *pde = 00000000 
[562980.584401] Oops: 0002 [#1] SMP 
[562980.584404] last sysfs file: /sys/devices/pci0000:00/0000:00:1f.1/host0/target0:0:0/0:0:0:0/block/sda/sda6/stat
[562980.584410] Dumping ftrace buffer:
[562980.584413]    (ftrace buffer empty)
[562980.584415] Modules linked in: ipw2200 michael_mic arc4 ecb ieee80211_crypt_tkip binfmt_misc lp i915 drm bnep vboxnetflt vboxdrv ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack ipt_REJECT xt_tcpudp iptable_filter ip_tables x_tables bridge stp snd_atiixp_modem snd_via82xx_modem snd_intel8x0m input_polldev tun deflate zlib_deflate ctr twofish twofish_common camellia serpent blowfish des_generic cbc aes_i586 aes_generic xcbc rmd160 sha256_generic sha1_generic crypto_null af_key dm_crypt joydev pcmcia snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm_oss snd_mixer_oss snd_pcm snd_seq_dummy snd_seq_oss snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device tifm_7xx1 iTCO_wdt iTCO_vendor_support snd soundcore tifm_core yenta_socket rsrc_nonstatic pcmcia_core ieee80211 ieee80211_crypt psmouse dcdbas pcspkr snd_page_alloc serio_raw shpchp intel_agp agpgart ppdev video output parport_pc parport b44 ssb mii ohci1394 ieee1394 raid
0 raid456 async_xor async_memcpy async_tx xor raid1 raid0 multipath linear fbcon tileblit font bitblit softcursor [last unloaded: ipw2200]
[562980.584495] 
[562980.584500] Pid: 26686, comm: ipw2200/0 Tainted: G        W  (2.6.28-13-generic #45-Ubuntu) Inspiron 700m      
[562980.584503] EIP: 0060:[<c0122c38>] EFLAGS: 00010082 CPU: 0
[562980.584506] EIP is at __ticket_spin_lock+0x8/0x20
[562980.584509] EAX: 000004a0 EBX: e28c0ce8 ECX: 00000000 EDX: 00000100
[562980.584512] ESI: 00000282 EDI: 00000000 EBP: e2831f10 ESP: e2831f10
[562980.584514]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[562980.584517] Process ipw2200/0 (pid: 26686, ti=e2830000 task=d0880c90 task.ti=e2830000)
[562980.584519] Stack:
[562980.584521]  e2831f18 c0122d58 e2831f28 c04fed3e e28c0ce8 e28c0cdc e2831f5c f7e0c950
[562980.584528]  e28c0cdc e28c0ce8 000004a0 f7e0ca60 e2831f48 e28c0cdc e2831f50 c04fd545
[562980.584534]  e28c0ce8 e28c0cdc f7e0ca60 e2831f6c f7e0ca89 e28c18a8 ecc4d780 e2831fa4
[562980.584541] Call Trace:
[562980.584543]  [<c0122d58>] ? default_spin_lock_flags+0x8/0x10
[562980.584547]  [<c04fed3e>] ? _spin_lock_irqsave+0x2e/0x40
[562980.584552]  [<f7e0c950>] ? ipw_rx_queue_replenish+0x20/0x130 [ipw2200]
[562980.584569]  [<f7e0ca60>] ? ipw_bg_rx_queue_replenish+0x0/0x40 [ipw2200]
[562980.584577]  [<c04fd545>] ? _cond_resched+0x35/0x50
[562980.584583]  [<f7e0ca60>] ? ipw_bg_rx_queue_replenish+0x0/0x40 [ipw2200]
[562980.584590]  [<f7e0ca89>] ? ipw_bg_rx_queue_replenish+0x29/0x40 [ipw2200]
[562980.584598]  [<c014afbd>] ? run_workqueue+0x8d/0x150
[562980.584602]  [<c014ef0a>] ? prepare_to_wait+0x3a/0x70
[562980.584607]  [<c014b238>] ? worker_thread+0x88/0xf0
[562980.584610]  [<c014ecb0>] ? autoremove_wake_function+0x0/0x50
[562980.584614]  [<c014b1b0>] ? worker_thread+0x0/0xf0
[562980.584617]  [<c014e90c>] ? kthread+0x3c/0x70
[562980.584621]  [<c014e8d0>] ? kthread+0x0/0x70
[562980.584624]  [<c0105477>] ? kernel_thread_helper+0x7/0x10
[562980.584628] Code: ff ff 90 b9 0a 2b 12 c0 b8 0d 2b 12 c0 e9 59 ff ff ff 90 b9 10 2b 12 c0 b8 13 2b 12 c0 e9 49 ff ff ff 90 55 ba 00 01 00 00 89 e5 <3e> 66 0f c1 10 38 f2 74 06 f3 90 8a 10 eb f6 5d c3 8d b4 26 00 
[562980.584663] EIP: [<c0122c38>] __ticket_spin_lock+0x8/0x20 SS:ESP 0068:e2831f10
[562980.584670] ---[ end trace 092d2ea3bba4a360 ]---