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Date:   Tue, 1 Aug 2023 10:57:26 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Leon Romanovsky <leon@kernel.org>
Cc:     Lin Ma <linma@zju.edu.cn>, davem@davemloft.net,
        edumazet@google.com, pabeni@redhat.com, fw@strlen.de,
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        chenzhongjin@huawei.com, aharonl@nvidia.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-rdma@vger.kernel.org
Subject: Re: [PATCH net v1 1/2] netlink: let len field used to parse
 type-not-care nested attrs
Message-ID: <20230801105726.1af6a7e1@kernel.org>
In-Reply-To: <20230801081117.GA53714@unreal>
References: <20230731121247.3972783-1-linma@zju.edu.cn>
        <20230731120326.6bdd5bf9@kernel.org>
        <20230801081117.GA53714@unreal>
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On Tue, 1 Aug 2023 11:11:17 +0300 Leon Romanovsky wrote:
> IMHO, you are lowering too much the separation line between simple vs.
> advanced use cases. 
> 
> I had no idea that my use-case of passing nested netlink array is counted
> as advanced usage.

Agreed, that's a fair point. I'm guessing it was inspired by the
ethtool stats? (Which in hindsight were a mistake on my part.)

For the longest time there was no docs or best practices for netlink.
We have the documentation and more infrastructure in place now.
I hope if you wrote the code today the distinction would have been
clearer.

If we start adding APIs for various one-(two?)-offs from the past
we'll never dig ourselves out of the "no idea what's the normal use
of these APIs" hole..