Re: INFO: rcu detected stall in xfrm_hash_rebuild

From: Florian Westphal
Date: Mon Dec 10 2018 - 07:47:36 EST

syzbot <syzbot+592df0494801b6648ec6@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> Hello,
> syzbot found the following crash on:

> Workqueue: events xfrm_hash_rebuild

Ignoring this report for a second -- I think it makes sense to see
if we can just remove the entire hash table rebuild/resize code.

After recent tree conversion, we could probably make the exact policies
part of the 'inexact tree' (which would be renamed to 'policy tree' or
some such).

Special-casing the exact policies made a lot of sense when we had
a single list for the inexact policies (to keep its length down).

But now I think we could try to unify all of this and only maintain
the existing tree-based storage.

Would also remove the need to do lookups in two different
data structures (bydst-hash-then-inexact-tree).

What do you think?