Oops while unloading module

Oops while unloading module

[Gaël Deest]

I first apologize for my approximative english.

I will soon get a Logitech Quickcam pro 4000, so I compiled my kernel 
with the PWC driver for Philips webcams (built-in). In addition, I tried 
to load the external (and closed-source) pwcx module (without the webcam 
plugged-in, of course). When I wanted to unload it with rmmod, it ended 
with "Segmentation fault" and I got the following Oops :

Dec 20 00:39:56 home kernel: Unable to handle kernel NULL pointer 
dereference at virtual address 00000000
Dec 20 00:39:56 home kernel:  printing eip:
Dec 20 00:39:56 home kernel: 00000000
Dec 20 00:39:56 home kernel: *pde = 00000000
Dec 20 00:39:56 home kernel: Oops: 0000 [#1]
Dec 20 00:39:56 home kernel: CPU:    0
Dec 20 00:39:56 home kernel: EIP:    0060:[<00000000>]    Tainted: PF
Dec 20 00:39:56 home kernel: EFLAGS: 00210246
Dec 20 00:39:56 home kernel: EIP is at 0x0
Dec 20 00:39:56 home kernel: eax: 00000000   ebx: e1a11d40   ecx: 
00000000   edx: e1a11d40
Dec 20 00:39:56 home kernel: esi: c045f718   edi: 00000000   ebp: 
00000880   esp: c2fadf5c
Dec 20 00:39:56 home kernel: ds: 007b   es: 007b   ss: 0068
Dec 20 00:39:56 home kernel: Process rmmod (pid: 13771, 
threadinfo=c2fac000 task=cfd4e040)
Dec 20 00:39:56 home kernel: Stack: c0133549 e1a11d40 bffff7b0 0000003b 
00000000 78637770 40016000 c0147787
Dec 20 00:39:56 home kernel:        df571100 c7da6700 c2454e80 40016000 
40017000 40017000 c2454e80 df571100
Dec 20 00:39:56 home kernel:        df571120 00000000 c2fac000 00147814 
df571100 bffff7b0 bffff7b0 00000880
Dec 20 00:39:56 home kernel: Call Trace:
Dec 20 00:39:56 home kernel:  [<c0133549>] sys_delete_module+0x119/0x190
Dec 20 00:39:56 home kernel:  [<c0147787>] do_munmap+0x147/0x190
Dec 20 00:39:56 home kernel:  [<c01091c7>] syscall_call+0x7/0xb
Dec 20 00:39:56 home kernel:
Dec 20 00:39:56 home kernel: Code:  Bad EIP value.

Then, I wanted to see if the module was here again and typed "lsmod", 
and it hanged. At this state, I can't load any other module because 
modprobe hangs too. My kernel is compiled with both "module unloading" 
and "forced module unloading."

If needed, may you tell me how I could provide further informations ?

Thanks :-) And great job for 2.6 anyway ;-)

Re: Oops while unloading module

[Greg KH]

On Sat, Dec 20, 2003 at 01:26:01PM +0100, Gaël Deest wrote:
> I first apologize for my approximative english.
> 
> I will soon get a Logitech Quickcam pro 4000, so I compiled my kernel 
> with the PWC driver for Philips webcams (built-in). In addition, I tried 
> to load the external (and closed-source) pwcx module (without the webcam 
> plugged-in, of course). When I wanted to unload it with rmmod, it ended 
> with "Segmentation fault" and I got the following Oops :

You'll have to ask the pwcx driver author about this, sorry.

greg k-h