From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 746764DC6B for ; Tue, 1 Aug 2023 19:49:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 41A2EC433C8; Tue, 1 Aug 2023 19:49:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690919394; bh=jx8nkKfZnsZVXx8umqQAQuPAq5SYkh1NN4szn/H3sNs=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bNwin6nzcMICQLvRxBzXlbrrbYS5mevgyW4ev5/p1V2gMZk4sp1hxPE+mQJk1ZUSK cAd8sET0dOL93qMWtn93DVNJhGN2P+bPFtVQYFCT2YoWV8hneWNw2y+yFGMofZmZkB KWbWZWrDtS2I23Ciuad/sQK+v3f2OW4TKFCW7rkL1mbXwL3jdko7ymdyFsJbwb4wp0 NEwCnVpazNzcNLEhqUeDrn5sMa56oXfo79yHbZrpCdmiVt/Clsy/5UAzLN0ab+c3b3 ICWtz1I8dvpIEWfbQla+77y7RyDmhcdrIjIUZO4wIvLkcXIO1zD74WT6hNR75qZr/S LQjwhqdGtjuAw== Date: Tue, 1 Aug 2023 22:49:49 +0300 From: Leon Romanovsky To: Jakub Kicinski Cc: Lin Ma , davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, fw@strlen.de, yang.lee@linux.alibaba.com, jgg@ziepe.ca, markzhang@nvidia.com, phaddad@nvidia.com, yuancan@huawei.com, ohartoov@nvidia.com, 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: <20230801194949.GC53714@unreal> References: <20230731121247.3972783-1-linma@zju.edu.cn> <20230731120326.6bdd5bf9@kernel.org> <20230801081117.GA53714@unreal> <20230801105726.1af6a7e1@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230801105726.1af6a7e1@kernel.org> On Tue, Aug 01, 2023 at 10:57:26AM -0700, Jakub Kicinski wrote: > 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.) I don't remember which part of kernel can be blamed for it. :) > > 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.. I agree with this sentence, just afraid that it is unrealistic goal, due to extensive flexibility in netlink UAPI toward user-space, which allows you to shoot yourself in the foot without even noticing it. Thanks