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 0A3AB63B3; Sat, 10 Feb 2024 05:01:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707541296; cv=none; b=KrgqQpZR4JQ9iP/Me5kGufKb9sDlFUvqLEaVFYfruR2yHLW/eEKUrDD0aF5Y666m+whaxTdD7pmOI4HoI1K3WfQGgV4oJ4K8ymR5glnfMxyvbISmr5PYMMwUO2TLW3YcbIM626b2tsKAXHpAcVuC9R/SZXWRE8Kf892agV4ubpE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707541296; c=relaxed/simple; bh=yW4SvVrA+uehcZQFBiIcKyOq0EVCxgF6A4J8ysbpmiA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fmjGr4OKN831LZiDEdFu6wmaQYHwxEX8+MXPuMW/HB3VjXRBkxjk0w4FFEzYiXYvXkrS/4aJkak6krkcL2VvFlJdJw0277lJSoYVOZDX82UIY38u1Wz3STp9ekN+JYRAGyVJM3z1HZkq7ML5c/o4zwGLcFtRD+J9DkXKnrQhdI0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oJWiDHWM; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oJWiDHWM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AE721C433F1; Sat, 10 Feb 2024 05:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1707541295; bh=yW4SvVrA+uehcZQFBiIcKyOq0EVCxgF6A4J8ysbpmiA=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=oJWiDHWMZ0LfZy1Zfi2dBv4UYV01xbt7wXuSND3b8/ImOt3cxgcVeqomVQTtFn5UB p8pI2WeLidOtXtg2LKs4P7KZoJ24uxYZWt4tt1hA8RMad4j9qxKnlKY+JpW/frjvb1 tZPA9WaN2pu/Lb8TgiKQbXEwU0s1DxqhaF5NzJwScFJ2+IwNICWPXikpwLRAuzRuWs IKwmdCUh7eJjb/6ADqlrUUjkL7pzAimfTQMLIObX4NTgAJwGOm8NunT+1pSvNjitoJ HQswCLOwClV7Bgp21pg8870MRvQcXuyxgVB1NMFdqQJXGg8G7LJTZZ3AExjh8VM40d bmwVOgMefYDQQ== Message-ID: Date: Fri, 9 Feb 2024 22:01:33 -0700 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH V4 0/5] mlx5 ConnectX control misc driver Content-Language: en-US To: Jakub Kicinski Cc: Saeed Mahameed , Arnd Bergmann , Greg Kroah-Hartman , Leon Romanovsky , Jason Gunthorpe , Jiri Pirko , Leonid Bloch , Itay Avraham , Saeed Mahameed , Aron Silverton , Christoph Hellwig , andrew.gospodarek@broadcom.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org References: <20240207072435.14182-1-saeed@kernel.org> <20240207070342.21ad3e51@kernel.org> <20240208181555.22d35b61@kernel.org> <2bdc5510-801a-4601-87a3-56eb941d661a@kernel.org> <20240209145828.30e1d000@kernel.org> From: David Ahern In-Reply-To: <20240209145828.30e1d000@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/9/24 3:58 PM, Jakub Kicinski wrote: > On Fri, 9 Feb 2024 15:42:16 -0700 David Ahern wrote: >> On 2/8/24 7:15 PM, Jakub Kicinski wrote: >>>> I was in the room and I am in support of David's idea, I like it a lot, >>>> but I don't believe we have any concrete proposal, and we don't have any >>>> use case for it in netdev for now, our use case for this is currently RDMA >>>> and HPC specific. >>>> >>>> Also siimilar to devlink we will be the first to jump in and implement >>>> the new API once defined, but this doesn't mean I need to throw away the >>> >>> I'm not asking to throw it away. The question is only whether you get >>> to push it upstream and skirt subsystem rules by posting a "misc" driver >>> without even CCing the maintainers on v1 :| >> >> Can you define what you mean by 'skirt subsystem rules'? That's a new >> one to me. > > I mean that Saeed is well aware that direct FW <> user space interfaces > are not allowed in netdev, so he posted this "misc" driver without > CCing us, knowing we'd nack it. The argument you are making here is that if a device has an ethernet port, all patches must flow through netdev. Or am I misunderstanding? There are a lot of devices that toggle between IB and ethernet with only one (ignore roce here) active at a moment. MLX5 (like many) is split between drivers/net and drivers/infinband. If the debugging capabilities went through drivers/infiniband would you have the same stance? Maybe my bigger question is should drivers that can do different physical layers, or can operate without a netdev, should they be split into different drivers? drivers/misc for the PCI interface, drivers/net for ethernet interfaces and its APIs and drivers/infiniband for IB and its APIs? Generic capabilities like this debugging interface belong to the PCI device since it is generic to the device hence drivers/misc. > > Maybe the baseline question is whether major subsystems are allowed to > set their own rules. I think they should as historically we have a very > broad range of, eh, openness in different fields. Networking is pretty > open because of the necessary interoperability. Interoperability applies solely to networking protocols, not how a device is designed and certainly not to how it can be debugged. There is a clear difference between standard networking protocols (packets on a wire and its headers) and device designs. > >> BTW, there is already a broadcom driver under drivers/misc that seems to >> have a lot of overlap capability wise to this driver. Perhaps a Broadcom >> person could chime in. > > I'm not aware. Or do you mean bcm-vk? That's a video encoder. If that specific piece of S/W is a video encoder, why isn't it under drivers/video? Scanning the code it seems to me to fall under the open channel between userspace and F/W which is a common paradigm. But I do not want this to distract from this patch set; really I was just browsing existing drivers for any overlap.