I got a nice segfault while using "rfcomm bind" tool from 
bluz-tools.Here is the trace:

  ------------[ cut here ]------------
kernel BUG at include/linux/module.h:294!
invalid operand: 0000 [#2]
CPU:    0
EIP:    0060:[<e10b3f58>]    Not tainted
EFLAGS: 00010246
EIP is at rfcomm_sock_alloc+0xe8/0x110 [rfcomm]
eax: 00000000   ebx: c6d371c0   ecx: c9e5c680   edx: c6d371c0
esi: 000000d0   edi: ffffff9f   ebp: d8533f00   esp: d8533ee8
ds: 007b   es: 007b   ss: 0068
Process rfcomm (pid: 30528, threadinfo=d8532000 task=c24be140)
Stack: e10b94c0 00000003 00000008 000000d0 fffffff4 ffffffa3 d8533f18 
e10b3fca
        c9e5c680 00000003 000000d0 00000003 d8533f30 e109a0c3 c9e5c680 
00000003
        0000001f c9e5c680 d8533f4c c02d6167 c9e5c680 00000003 00000000 
00000001
Call Trace:
  [<e10b94c0>] +0x0/0x140 [rfcomm]
  [<e10b3fca>] rfcomm_sock_create+0x4a/0x70 [rfcomm]
  [<e109a0c3>] bt_sock_create+0x53/0xa0 [bluetooth]
  [<c02d6167>] sock_create+0xa7/0x190
  [<c02d6279>] sys_socket+0x29/0x60
  [<c02d7205>] sys_socketcall+0x85/0x270
  [<c0140737>] sys_munmap+0x57/0x80
  [<c01090f3>] syscall_call+0x7/0xb

Code: 0f 0b 26 01 51 6c 0b e1 e9 72 ff ff ff 0f 0b cb 01 68 6c 0b