BUG: unable to handle kernel NULL pointer dereference at 00000004
IP: [<f807cbee>] acm_probe+0xee/0xce0 [cdc_acm]
*pde = 249a8067 *pte = 00000000 
Oops: 0000 [#1] SMP 
last sysfs file: /sys/devices/pci0000:00/0000:00:1d.1/usb3/bDeviceClass
Modules linked in: cdc_acm(+) nls_iso8859_1 nls_cp437 vfat fat binfmt_misc radeon snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi ttm snd_rawmidi drm_kms_helper ipw2200 snd_seq_midi_event snd_seq pcmcia libipw snd_timer snd_seq_device drm cfg80211 ppdev usb_storage intel_agp yenta_socket pcmcia_rsrc dcdbas snd video parport_pc joydev psmouse output pcmcia_core lib80211 i2c_algo_bit soundcore shpchp serio_raw snd_page_alloc agpgart lp parport usbhid b44 hid ssb mii

Pid: 2158, comm: modprobe Not tainted 2.6.35-22-generic #33-Ubuntu 0X8957/Inspiron 600m                   
EIP: 0060:[<f807cbee>] EFLAGS: 00010286 CPU: 0
EIP is at acm_probe+0xee/0xce0 [cdc_acm]
EAX: 00000000 EBX: e4112a00 ECX: 00000001 EDX: 00000001
ESI: 00000000 EDI: e4112a00 EBP: e4935e28 ESP: e4935dc0
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
Process modprobe (pid: 2158, ti=e4934000 task=d52c1960 task.ti=e4934000)
Stack:
 f807ef14 f807ee16 e9cb2390 00935df0 00000001 00000009 00000001 e4935de4
<0> c012ce18 e4935dec c012ce18 e4935e00 c05c8b9f e4935e00 e9cb2390 e4112a1c
<0> 00000010 e40e4064 e40e4000 e40e400f 00000000 00000000 00000000 e4112a00
Call Trace:
 [<c012ce18>] ? default_spin_lock_flags+0x8/0x10
 [<c012ce18>] ? default_spin_lock_flags+0x8/0x10
 [<c05c8b9f>] ? _raw_spin_lock_irqsave+0x2f/0x50
 [<c0475a3c>] ? usb_probe_interface+0xec/0x1b0
 [<c0271ed7>] ? sysfs_create_link+0x17/0x20
 [<c0400550>] ? really_probe+0x50/0x150
 [<c0407bc7>] ? pm_runtime_barrier+0x57/0xb0
 [<c040068c>] ? driver_probe_device+0x3c/0x60
 [<c0400731>] ? __driver_attach+0x81/0x90
 [<c03ffb53>] ? bus_for_each_dev+0x53/0x80
 [<c040041e>] ? driver_attach+0x1e/0x20
 [<c04006b0>] ? __driver_attach+0x0/0x90
 [<c03ffde5>] ? bus_add_driver+0xd5/0x280
 [<c0400a2a>] ? driver_register+0x6a/0x130
 [<c0475751>] ? usb_register_driver+0x81/0x130
 [<c03d9d72>] ? tty_register_driver+0xf2/0x1c0
 [<c03da8c1>] ? alloc_tty_driver+0x51/0x70
 [<f80aa0a1>] ? acm_init+0xa1/0xd0 [cdc_acm]
 [<c0101132>] ? do_one_initcall+0x32/0x1a0
 [<f80aa000>] ? acm_init+0x0/0xd0 [cdc_acm]
 [<c0180c2b>] ? sys_init_module+0x9b/0x1e0
 [<c0218fa2>] ? sys_write+0x42/0x70
 [<c05c90a4>] ? syscall_call+0x7/0xb
Code: 07 29 c1 85 c9 7f cf 85 f6 0f 85 9e 01 00 00 85 d2 0f 8e 54 01 00 00 8b 45 e0 89 df e8 8c ce 3e c8 89 c6 39 f7 0f 84 09 03 00 00 <8b> 46 04 80 78 05 0a 0f 84 ed 00 00 00 8b 47 04 80 78 05 0a 0f 
EIP: [<f807cbee>] acm_probe+0xee/0xce0 [cdc_acm] SS:ESP 0068:e4935dc0
CR2: 0000000000000004
---[ end trace ffd50f091196339d ]---