Re: kernel BUG at mm/slab.c:1488! (2.6.13.2)

[Davi Arnaut <davi.lkml@gmail.com>]

On 10/28/05, Andrew Morton <akpm@osdl.org> wrote:
> Davi Arnaut <davi.lkml@gmail.com> wrote:
> >
> >  > It seems that something still tries to load the ext3 module, and I get the
> >  > BUG seen below.  If I remove the ext3 module and re-build the initrd,
> >  > the error goes away.
>
> Yes, I think the kernel is overreacting here.
>
> Manfred, what sayest thou?
>
> (nb: untested)
>
>
> From: Andrew Morton <akpm@osdl.org>
>
> slab presently goes BUG if someone tries to register an already-registered
> cache.
>
> But this can happen if the user accidentally loads a module which is already
> statically linked into the kernel.  Nuking the kernel is rather a harsh
> reaction.
>
> Change it into a warning, and just fail the kmem_cache_alloc() attempt.  If
> the module is well-behaved, the modprobe will fail and all is well.

How about really fixing kmem_cache_* to use the proper return conventions ?
In this case it should have returned ERR_PTR(-EEXIST);

> Notes:
>
> - Swaps the ranking of cache_chain_sem and lock_cpu_hotplug().  Doesn't seem
>   important.
>
>
> <sniped>
>