Re: Debugging memory allocation

[Paul M. <le...@li...>]

On Wed, Sep 12, 2007 at 08:50:33PM +0100, Adrian McMenamin wrote:
> I don't know if this is just G2 flakiness, but if I start playing sound
> and then start hotplugging devices then I will sometimes get this sort
> of oops (these don't down the system but they can make it unstable) -
> any clues as to what might be the issue (these are now quite old -rc2?
> kernels...)... just wondering if anybody can see anything obvious?
> 
> [   95.916012] Maple bus detaching at (0, 2)
> [   96.208858] Unable to handle kernel paging request at virtual address
> dfff0800
> [   96.215707] pc = 8c00e480
> [   96.218317] *pde = 00000000
> [   96.221194] Oops: 0001 [#1]
> [   96.224005] Modules linked in: snd_aica snd_pcm_oss snd_pcm snd_timer
> snd_page_alloc snd_mixer_oss snd soundcore maple_keyb
> [   96.235500] 
> [   96.237035] Pid : 1842, Comm:                    [
> [   96.241993] PC is at __copy_user_page+0x28/0x54

You've faulted on a fixmap slot, perhaps you've hit a race with the page
colouring code. Can you try with write-through caching enabled?