kernel oops after unloading driver module

["Mandeep Singh Sandhu" <mandeep_sandhu@xxxxxxxxxxx>]

Hi all,

I'm writing a serial port driver for 16550A UART on a 2.4.18 kernel
for learning purpose. The problem i'm facing is that after i remove
my module (rmmod it) and then run the userspace program that
tries to open my device (ttyS0 - IRQ 4) the kernel oops saying
"Unable to handle virtual page request at - <some address>
EIP .....
irq handler - not syncing"

The address that it displays during oops is the address that is
shown in /proc/ksyms file against my IRQ handler before i removed
my module. I'm attaching my driver file as well as the userspace
prog. i used to test it with (zipped). It's based on serial.c
(u'll find some uneccessary code in it, which u ignore). If somebody
could tell me what i'm doing wrong.......

btw i've compiled my kernel with support for 8250, 16550... UARTs

TIA
- /dev/mandeep

 <<serial.zip>>

serial.zip