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Date: Wed, 24 Jul 2024 09:51:42 +0200
From: Pablo Neira Ayuso <pablo@netfilter.org>
To: Phil Sutter <phil@nwl.cc>, Eric Garver <eric@garver.life>,
	netfilter-devel@vger.kernel.org, nhofmeyr@sysmocom.de
Subject: Re: [PATCH nft 2/2,v2] cache: recycle existing cache with
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On Tue, Jul 23, 2024 at 05:09:12PM +0200, Phil Sutter wrote:
[...]
> I don't like the commit because it breaks with the assumption that
> kernel genid matching cache genid means cache is up to date. It may
> indeed be, but I think it's thin ice and caching code is pretty complex
> as-is. :/

Right.

It is possible to retrieve the generation ID from the batch via
NLM_F_ECHO and the NFT_MSG_GETGEN to answer the question: "Was it
myself that has updated the ruleset last time?".

And this needs a lot more tests for -i/--interactive which is a
similar path to what daemons will exercise to ensure cache
consistency.