Jarek Poplawski wrote:

On Mon, Jun 02, 2008 at 12:43:42PM +0200, Patrick McHardy wrote:

quoted

Jarek Poplawski wrote:

quoted

According to this and another similar lockdep report inet_fragment
locks are taken from nf_ct_frag6_gather() with softirqs enabled, but
these locks are mainly used in softirq context, so disabling BHs is
necessary.

Yes, this can happen on the local output path,

quoted

David & Patrick,

It looks like this patch could be applied.

Looks mostly fine, but don't we also have to disable BHs for
the inet_frag_find() call in nf_ct_frag6_gather()?

Probably I miss something, but I think this patch seems to do it:
I can see only one such call in nf_ct_frag6_gather() - with
fq_find()?

Right, I missed that, sorry.

BTW, it looks like this lockdep warning points at some other possible
problem: inet_fragment.c uses an SMP "optimization" in
inet_frag_intern(), probably assuming softirq context; so without such
BH blocking around inet_frag_find(), there should be at least
preemption disabled, but I don't know if it's a problem for nf_ct.

Yes, good catch. With your patch things should be fine however.

I've applied your patch and will also push it to -stable.