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Date:   Mon, 10 Dec 2018 13:47:24 +0100
From:   Florian Westphal <fw@strlen.de>
To:     syzbot <syzbot+592df0494801b6648ec6@syzkaller.appspotmail.com>
Cc:     davem@davemloft.net, herbert@gondor.apana.org.au,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        steffen.klassert@secunet.com, syzkaller-bugs@googlegroups.com
Subject: Re: INFO: rcu detected stall in xfrm_hash_rebuild
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syzbot <syzbot+592df0494801b6648ec6@syzkaller.appspotmail.com> 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?