app中调用ioctl函数的错误！！！

我在app中调用ioctl函数，运行app后终端提示：segmentation fault
查看message，信息如下：
10:45:19 gconfd (root-783): Failed to send buffer
May 23 10:45:49 localhost kernel: app call driver open.
May 23 10:45:49 localhost kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000
May 23 10:45:49 localhost kernel:  printing eip:
May 23 10:45:49 localhost kernel: c89be72f
May 23 10:45:49 localhost kernel: *pde = 00000000
May 23 10:45:49 localhost kernel: Oops: 0000
May 23 10:45:49 localhost kernel: card ide-cd cdrom esssolo1 gameport soundcore autofs ds yenta_socket pcmcia_co
May 23 10:45:49 localhost kernel: CPU:    0
May 23 10:45:49 localhost kernel: EIP:    0010:[<c89be72f>]    Not tainted
May 23 10:45:49 localhost kernel: EFLAGS: 00210292
May 23 10:45:49 localhost kernel:
May 23 10:45:49 localhost kernel: EIP is at __create_pipe [card] 0x9 (2.4.18-14)
May 23 10:45:49 localhost kernel: eax: 00000000   ebx: ffffffe7   ecx: 00000000   edx: 4202b225
May 23 10:45:50 localhost kernel: esi: 00000048   edi: c7169560   ebp: c2fcff30   esp: c2fcff2c
May 23 10:45:50 localhost kernel: ds: 0018   es: 0018   ss: 0018
May 23 10:45:50 localhost kernel: Process test2 (pid: 1066, stackpage=c2fcf000)
May 23 10:45:50 localhost kernel: Stack: c2fce000 c2fcff90 c89be46d 00000000 00000000 000000c3 00000040 0000f0b3
May 23 10:45:50 localhost kernel:        0000000f 00000000 00000000 00000a00 4202b21d 00000000 c0f0a000 c582dc40
May 23 10:45:50 localhost kernel:        ffffffea 00000010 c017a75d f0b3c381 ec83000f d9c0dc40 c2fce000 c48dd9c0
May 23 10:45:50 localhost kernel: Call Trace: [<c89be46d>] usb_ioctl [card] 0x6b (0xc2fcff34))
May 23 10:45:50 localhost kernel: [<c017a75d>] tty_write [kernel] 0xfd (0xc2fcff74))
May 23 10:45:50 localhost kernel: [<c014ee83>] sys_ioctl [kernel] 0xc3 (0xc2fcff94))
May 23 10:45:50 localhost kernel: [<c010910f>] system_call [kernel] 0x33 (0xc2fcffc0))
May 23 10:45:50 localhost kernel:
May 23 10:45:50 localhost kernel:
May 23 10:45:50 localhost kernel: Code: 8b 00 c1 e0 08 8b 55 0c c1 e2 0f 09 d0 89 45 fc 8b 45 08 83

不知何故，请高手指点！！

你的app是干什么的？