From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 754A6C433E2 for ; Wed, 16 Sep 2020 08:03:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3B83B21D24 for ; Wed, 16 Sep 2020 08:03:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kuIn3pJp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726412AbgIPIDl (ORCPT ); Wed, 16 Sep 2020 04:03:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726541AbgIPIDf (ORCPT ); Wed, 16 Sep 2020 04:03:35 -0400 Received: from mail-oi1-x242.google.com (mail-oi1-x242.google.com [IPv6:2607:f8b0:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C2E5C06174A; Wed, 16 Sep 2020 01:03:07 -0700 (PDT) Received: by mail-oi1-x242.google.com with SMTP id i16so1729014oii.12; Wed, 16 Sep 2020 01:03:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=lmpE7Zf045Vv00K6sEaHXo64+zEBp0yhPWRBeLSTcn0=; b=kuIn3pJpGJ+mpkQyhF710YhlvD1LVwbS+RTByqTFNLD49Jem0MDX+aDtN3XDVKSjVC 7xMMr1wLVTprF2yesOSOzRXOXPsgIRAgttbC36inMn4N4Z3yUdn9KmGtTY4hYIZsUwGC vsx9XE1/bwypsv5YJT8sWRIK+pZaBWnf3mwjyLNLRZIz/LUZwKFZa9A6Za6NXMS4UbHE K7JB5rrTr53FVtvcaOXdrsOOgAACwe9UZg5Yk3qbRUOyTkLFvC9MR9Sr9lN37cdE7j11 K176XvPct2UBtyXlKihm9JKofLELIIDIZJkBkJo5RrCeimpLZ90Nk8t4/OQ9O5DYnSxy /Pjg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=lmpE7Zf045Vv00K6sEaHXo64+zEBp0yhPWRBeLSTcn0=; b=WRpehHdx+kNYTdn6/gRlXA98oHQLiCmLjQbYXNgbz0KQKa3t7YNwZr8dM26FVyAeN9 A9kFZrJNH4zV8WP3zaDx8xldOaHhLRHKAdJwdy3ZCktBURUeBPGfITbZtO8Ew35+iEQV 3wARkX4O+r1GZh7XqZVjsKmWFthUEAYLLWZaoSL2+HV0Trh61Ots7+92PmOlDtdIUnwt bszPypKKeIIJ2uDMHeOcaFtVQMV8DygyaZUaIiLpskQCTbYqeB866IX5DIi+hh6TKnbM YFs1rOp6UrVnvvFIDrZgZVjdAzo5oR/liHzGG2hap4VNBtAV5f+F895Raf1/emkqlP0d mA2Q== X-Gm-Message-State: AOAM531LvHYpjDP2rF0fWPFjl2o0nWkzhy2fVZ1gyX3ekarw5Cok67Zz J/J5i0kU6DJoyYMu1hERQZpsH5xTk3KC3F/DFcFV/emI4EnMLA== X-Google-Smtp-Source: ABdhPJy0d4x7g48hIPo/6h8BE8KloT2VJFeG1CSKsxy395xfz4UzMudOhX0Z8FA6d9JbI5RT1bfPgZ8o8WONtmqfknk= X-Received: by 2002:a05:6808:3bb:: with SMTP id n27mr2211314oie.130.1600243386330; Wed, 16 Sep 2020 01:03:06 -0700 (PDT) MIME-Version: 1.0 References: <20200915171022.10561-1-oded.gabbay@gmail.com> <20200915.134252.1280841239760138359.davem@davemloft.net> <20200916062614.GF142621@kroah.com> <20200916074217.GB189144@kroah.com> In-Reply-To: <20200916074217.GB189144@kroah.com> From: Oded Gabbay Date: Wed, 16 Sep 2020 11:02:39 +0300 Message-ID: Subject: Re: [PATCH v3 00/14] Adding GAUDI NIC code to habanalabs driver To: Greg Kroah-Hartman Cc: David Miller , "Linux-Kernel@Vger. Kernel. Org" , netdev@vger.kernel.org, SW_Drivers , Jakub Kicinski , Andrew Lunn , Florian Fainelli Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 16, 2020 at 10:41 AM Greg Kroah-Hartman wrote: > > On Wed, Sep 16, 2020 at 09:36:23AM +0300, Oded Gabbay wrote: > > On Wed, Sep 16, 2020 at 9:25 AM Greg Kroah-Hartman > > wrote: > > > > > > On Tue, Sep 15, 2020 at 11:49:12PM +0300, Oded Gabbay wrote: > > > > On Tue, Sep 15, 2020 at 11:42 PM David Miller wrote: > > > > > > > > > > From: Oded Gabbay > > > > > Date: Tue, 15 Sep 2020 20:10:08 +0300 > > > > > > > > > > > This is the second version of the patch-set to upstream the GAUDI NIC code > > > > > > into the habanalabs driver. > > > > > > > > > > > > The only modification from v2 is in the ethtool patch (patch 12). Details > > > > > > are in that patch's commit message. > > > > > > > > > > > > Link to v2 cover letter: > > > > > > https://lkml.org/lkml/2020/9/12/201 > > > > > > > > > > I agree with Jakub, this driver definitely can't go-in as it is currently > > > > > structured and designed. > > > > Why is that ? > > > > Can you please point to the things that bother you or not working correctly? > > > > I can't really fix the driver if I don't know what's wrong. > > > > > > > > In addition, please read my reply to Jakub with the explanation of why > > > > we designed this driver as is. > > > > > > > > And because of the RDMA'ness of it, the RDMA > > > > > folks have to be CC:'d and have a chance to review this. > > > > As I said to Jakub, the driver doesn't use the RDMA infrastructure in > > > > the kernel and we can't connect to it due to the lack of H/W support > > > > we have > > > > Therefore, I don't see why we need to CC linux-rdma. > > > > I understood why Greg asked me to CC you because we do connect to the > > > > netdev and standard eth infrastructure, but regarding the RDMA, it's > > > > not really the same. > > > > > > Ok, to do this "right" it needs to be split up into separate drivers, > > > hopefully using the "virtual bus" code that some day Intel will resubmit > > > again that will solve this issue. > > Hi Greg, > > Can I suggest an alternative for the short/medium term ? > > > > In an earlier email, Jakub said: > > "Is it not possible to move the files and still build them into a single > > module?" > > > > I thought maybe that's a good way to progress here ? > > Cross-directory builds of a single module are crazy. Yes, they work, > but really, that's a mess, and would never suggest doing that. > > > First, split the content to Ethernet and RDMA. > > Then move the Ethernet part to drivers/net but build it as part of > > habanalabs.ko. > > Regarding the RDMA code, upstream/review it in a different patch-set > > (maybe they will want me to put the files elsewhere). > > > > What do you think ? > > I think you are asking for more work there than just splitting out into > separate modules :) > > thanks, > > greg k-h Hi Greg, If cross-directory building is out of the question, what about splitting into separate modules ? And use cross-module notifiers/calls ? I did that with amdkfd and amdgpu/radeon a couple of years back. It worked (that's the best thing I can say about it). The main problem with this "virtual bus" thing is that I'm not familiar with it at all and from my experience I imagine it would take a considerable time and effort to upstream this infrastructure work. This could delay the NIC code for a couple of years, which by then this won't be relevant at all. So I'm trying to find some middle ground here on how to proceed. Thanks, Oded