Description of problem:

I used bluetooth (usb dongle)/rfcomm and wvdial to go online with my nokia.
Currently installed kernel is kernel-2.6.18-1.2693.fc6 (from devel tree of fc6).
Today morning got ppp0 down and zombie wvdial (killall -9 wvdial can't kill!).

BUG: unable to handle kernel NULL pointer dereference at virtual address 
00000018

Version-Release number of selected component (if applicable):
kernel-2.6.18-1.2693.fc6
bluez-libs-3.0-3
wvdial-1.54.0-5.2.2.1

How reproducible:
unable to reproduce for this moment


Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:

dmesg:

BUG: unable to handle kernel NULL pointer dereference at virtual address 
00000018                                            
 printing eip:
f8b51231
*pde = 2e505067
Oops: 0000 [#1]
SMP 
last sysfs file: /class/tty/rfcomm0/dev
Modules linked in: ppp_deflate zlib_deflate ppp_async crc_ccitt ppp_generic 
slhc i915 drm ipt_REJECT ipt_owner xt_multiport iptable_filter ip_tables 
x_tables tun ipw3945(U) ieee80211 ieee80211_crypt pcc_acpi(U) ipv6 rfcomm l2cap 
cpufreq_ondemand cryptoloop aes_i586 loop dm_mirror dm_mod video sbs i2c_ec 
battery asus_acpi ac parport_pc lp parport snd_hda_intel snd_hda_codec 
snd_seq_dummy snd_seq_oss joydev snd_seq_midi_event snd_seq snd_seq_device 
snd_pcm_oss snd_mixer_oss snd_pcm sg snd_timer snd i2c_i801 pcspkr i2c_core 
soundcore snd_page_alloc sdhci sky2 mmc_core hci_usb bluetooth serio_raw ext3 
jbd ahci libata usb_storage sd_mod scsi_mod ohci_hcd uhci_hcd ehci_hcd
CPU:    1
EIP:    0060:[<f8b51231>]    Not tainted VLI
EFLAGS: 00210282   (2.6.18-1.2693.fc6 #1) 
EIP is at rfcomm_send_rpn+0xb/0xa7 [rfcomm]
eax: 00000000   ebx: 00000003   ecx: 00000004   edx: 00000001
esi: 00000003   edi: 00000001   ebp: d036bd98   esp: d036bd7c
ds: 007b   es: 007b   ss: 0068
Process wvdial (pid: 32058, ti=d036b000 task=cd8f8ab0 task.ti=d036b000)
Stack: 00000000 c06981d4 cd8f8ab0 00000000 00000003 00000003 00000003 d036bdf4 
       f8b54559 00000003 00000003 00000000 00000000 00000000 00000011 00000013 
       00000001 d036be08 d7b26234 00000030 00000000 0001c200 d036bd00 00200286 
Call Trace:
 [<f8b54559>] rfcomm_tty_set_termios+0x1bb/0x1c6 [rfcomm]
 [<c0537362>] set_termios+0x2f1/0x336
 [<c05374c8>] n_tty_ioctl+0x121/0x45a
 [<c0534b31>] tty_ioctl+0xcaa/0xd0b
 [<c0483172>] do_ioctl+0x4e/0x67
 [<c04833e3>] vfs_ioctl+0x258/0x26b
 [<c048343d>] sys_ioctl+0x47/0x62
 [<c0403fb7>] syscall_call+0x7/0xb
DWARF2 unwinder stuck at syscall_call+0x7/0xb
Leftover inexact backtrace:
 [<c0405389>] show_stack_log_lvl+0x8a/0x95
 [<c04054c1>] show_registers+0x12d/0x19a
 [<c04056be>] die+0x190/0x293
 [<c0615d8d>] do_page_fault+0x3dc/0x4a4
 [<c0404be9>] error_code+0x39/0x40
 [<f8b54559>] rfcomm_tty_set_termios+0x1bb/0x1c6 [rfcomm]
 [<c0537362>] set_termios+0x2f1/0x336
 [<c05374c8>] n_tty_ioctl+0x121/0x45a
 [<c0534b31>] tty_ioctl+0xcaa/0xd0b
 [<c0483172>] do_ioctl+0x4e/0x67
 [<c04833e3>] vfs_ioctl+0x258/0x26b
 [<c048343d>] sys_ioctl+0x47/0x62
 [<c0403fb7>] syscall_call+0x7/0xb
Code: 83 f2 ef 0f b6 d2 8a 92 c0 4f b5 f8 f7 d2 88 55 ef 8d 55 e8 e8 56 ff ff 
ff 83 c4 10 5b 5e 5d c3 55 89 e5 57 89 d7 56 53 83 ec 10 <8b> 70 18 8a 5d 0c c1 
e1 02 83 c9 03 88 4d e9 01 f6 83 ce 01 83 
EIP: [<f8b51231>] rfcomm_send_rpn+0xb/0xa7 [rfcomm] SS:ESP 0068:d036bd7c

 cat /proc/version 
Linux version 2.6.18-1.2693.fc6 (brewbuilder.redhat.com) (gcc 
version 4.1.1 20060920 (Red Hat 4.1.1-24)) #1 SMP Fri Sep 22 18:03:54 EDT 2006

 cat /proc/cpuinfo |grep name
model name      : Genuine Intel(R) CPU           T2400  @ 1.83GHz
model name      : Genuine Intel(R) CPU           T2400  @ 1.83GHz

lspci |grep -i usb
00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #1 (rev 
02)
00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #2 (rev 
02)
00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #3 (rev 
02)
00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI #4 (rev 
02)
00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI 
Controller (rev 02)
0e:00.0 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 
Controller (rev 61)
0e:00.1 USB Controller: VIA Technologies, Inc. VT82xxxxx UHCI USB 1.1 
Controller (rev 61)


cat /proc/modules:

 cat /proc/modules 
ipw3945 199128 1 - Live 0xf8b6d000
ieee80211 35729 1 ipw3945, Live 0xf8b3d000
ieee80211_crypt 10561 1 ieee80211, Live 0xf8a37000
ppp_deflate 10433 0 - Live 0xf8c59000
zlib_deflate 23001 1 ppp_deflate, Live 0xf8c71000
ppp_async 16857 1 - Live 0xf8c6b000
crc_ccitt 6337 1 ppp_async, Live 0xf8c56000
ppp_generic 33541 6 ppp_deflate,ppp_async, Live 0xf8c61000
slhc 10945 1 ppp_generic, Live 0xf8c52000
i915 24129 2 - Live 0xf8bb7000
drm 74613 3 i915, Live 0xf8c39000
ipt_REJECT 9921 3 - Live 0xf8b9f000
ipt_owner 6209 1 - Live 0xf8b5c000
xt_multiport 7617 5 - Live 0xf8b1f000
iptable_filter 7361 1 - Live 0xf8aaa000
ip_tables 17925 1 iptable_filter, Live 0xf8ba6000
x_tables 18901 4 ipt_REJECT,ipt_owner,xt_multiport,ip_tables, Live 0xf8b51000
ipv6 274593 46 - Live 0xf8bbf000
rfcomm 47209 5 - Live 0xf8b60000
l2cap 32721 7 rfcomm, Live 0xf8b48000
cpufreq_ondemand 11341 2 - Live 0xf8af7000
dm_mirror 34449 0 - Live 0xf8b33000
dm_mod 63865 1 dm_mirror, Live 0xf8b22000
video 21701 0 - Live 0xf8b06000
sbs 20877 0 - Live 0xf8aff000
i2c_ec 9409 1 sbs, Live 0xf8af3000
battery 14789 0 - Live 0xf8aa5000
asus_acpi 21337 0 - Live 0xf8ac2000
ac 9669 0 - Live 0xf8a4b000
parport_pc 32229 0 - Live 0xf8ab9000
lp 17577 0 - Live 0xf89c5000
parport 41769 2 parport_pc,lp, Live 0xf8aad000
snd_hda_intel 23141 1 - Live 0xf8a98000
snd_hda_codec 158065 1 snd_hda_intel, Live 0xf8acb000
snd_seq_dummy 8133 0 - Live 0xf89e2000
snd_seq_oss 38737 0 - Live 0xf8a58000
snd_seq_midi_event 12105 1 snd_seq_oss, Live 0xf89bc000
snd_seq 59161 5 snd_seq_dummy,snd_seq_oss,snd_seq_midi_event, Live 0xf8a88000
snd_seq_device 13141 3 snd_seq_dummy,snd_seq_oss,snd_seq, Live 0xf8a15000
snd_pcm_oss 47457 0 - Live 0xf8a7b000
snd_mixer_oss 21065 2 snd_pcm_oss, Live 0xf8a30000
snd_pcm 82669 3 snd_hda_intel,snd_hda_codec,snd_pcm_oss, Live 0xf8a65000
joydev 13825 0 - Live 0xf8a10000
snd_timer 27741 2 snd_seq,snd_pcm, Live 0xf8a28000
snd 59269 9 
snd_hda_intel,snd_hda_codec,snd_seq_oss,snd_seq,snd_seq_device,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_timer,
 Live 0xf8a3b000
sg 39269 0 - Live 0xf8a1d000
soundcore 14369 2 snd, Live 0xf89dd000
pcspkr 7489 0 - Live 0xf88fd000
snd_page_alloc 14665 2 snd_hda_intel,snd_pcm, Live 0xf89d8000
sdhci 23393 0 - Live 0xf8a09000
sky2 45269 0 - Live 0xf89cb000
i2c_i801 12237 0 - Live 0xf8991000
mmc_core 31305 1 sdhci, Live 0xf8997000
i2c_core 26321 2 i2c_ec,i2c_i801, Live 0xf8832000
hci_usb 22029 3 - Live 0xf8985000
serio_raw 11589 0 - Live 0xf8981000
bluetooth 60485 7 rfcomm,l2cap,hci_usb, Live 0xf88c8000
ext3 139001 3 - Live 0xf89e6000
jbd 64545 1 ext3, Live 0xf88ec000
ahci 23621 2 - Live 0xf88c1000
libata 105825 1 ahci, Live 0xf89a1000
usb_storage 75201 0 - Live 0xf88d8000
sd_mod 25537 3 - Live 0xf8878000
scsi_mod 142761 5 sg,ahci,libata,usb_storage,sd_mod, Live 0xf8854000
ohci_hcd 25701 0 - Live 0xf884c000
uhci_hcd 28501 0 - Live 0xf8844000
ehci_hcd 36437 0 - Live 0xf883a000