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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 0FDD6C4321A for ; Fri, 28 Jun 2019 23:05:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D16842086D for ; Fri, 28 Jun 2019 23:05:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pzwBCZ+h" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726862AbfF1XFS (ORCPT ); Fri, 28 Jun 2019 19:05:18 -0400 Received: from mail-lj1-f194.google.com ([209.85.208.194]:40771 "EHLO mail-lj1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726643AbfF1XFS (ORCPT ); Fri, 28 Jun 2019 19:05:18 -0400 Received: by mail-lj1-f194.google.com with SMTP id a21so7500601ljh.7 for ; Fri, 28 Jun 2019 16:05:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=GqfzcGTh4R+wjudzcyBPWjah+lJ5/F0fn2v7GiYZZ1A=; b=pzwBCZ+hEhuF0BWeVUfu6SkZIpY1bN87/e7nB8Y+GdcMuWSa97E/Uf5YhCv+jn4ha6 e//1PWFAausGWjhzQ1oVU6YvJ8VkrbqAPRNMtkMBAwP6lhw2P2T/SwZt1mZJD/X7n/vQ OuwSNuRcqVhUeBZaud3kV5x1gnG7g2bVZTPUDuXw7B40081EL20cZfe2AChoXMxFRmVM h7xKhLdNj9kWC3CRZLCr0zjiKMBJ0CyBjC5U3cJdTZqvpA0DHcKT22Aen4UtdO8N6cv2 EBRfiV6b69wnobETdZwwad4vP31sRQM/TyOHaHWKPAMRYT6rcQM/SZbqHMVknzgebqa8 QypA== 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=GqfzcGTh4R+wjudzcyBPWjah+lJ5/F0fn2v7GiYZZ1A=; b=QyZcQROBD/ExcX3vVttXpO0ffUKNjQI2rytWI4Srli4t4yn7Nu0v8s64+uetzj0i4o 0YXlg053XnQ9ntVWT9+cdd+p3yCRogRrpXLRIf9dJF2MFFw1hqwW53cbPWHZmjR2xET4 QmFB94/7KSQjEi2Q26bJzhe/it5oLD3OwdmaDzYtq7oyNY2tsX5p0nbib7Bz15lR3XKN h8P3dHI1ooPz58RYHnPgFvSO6HtqutrlhjqyZ4xyWJz4yLNhzcTticjCLm2VfA2B/oJY 4lWw2erQi0lYkoCZdIcpCY0cxjaqhZsd9BGtLPqpdXld7ne4ScMSJ4amf2VUPCmwmCIF dd2Q== X-Gm-Message-State: APjAAAWLoJZ5ewPqDdzEnSTySLlv+ERNl2+Sb0sl4vVOT58kvXZcgc30 6ktwLdHtdIdkwHFK3OoVcFjlxM4YKtQGOhBx4UCVfRtP0DnZAw== X-Google-Smtp-Source: APXvYqyb+IODZkDaSzeYM2z+Z6NUQ7nHDLo8t8QrnPDdXxpufnA1F1qjEioD/oQWkrnwtYqxsbD2prYuA8maHYT2544= X-Received: by 2002:a2e:5b1b:: with SMTP id p27mr7304303ljb.97.1561763116214; Fri, 28 Jun 2019 16:05:16 -0700 (PDT) MIME-Version: 1.0 References: <20190626185251.205687-1-csully@google.com> <20190626185251.205687-2-csully@google.com> <20190626160832.3f191a53@cakuba.netronome.com> <20190628114615.4fc81791@cakuba.netronome.com> <20190628200628.GS27733@lunn.ch> In-Reply-To: <20190628200628.GS27733@lunn.ch> From: Catherine Sullivan Date: Fri, 28 Jun 2019 16:05:05 -0700 Message-ID: Subject: Re: [net-next 1/4] gve: Add basic driver framework for Compute Engine Virtual NIC To: Andrew Lunn Cc: Jakub Kicinski , netdev@vger.kernel.org, Sagi Shahar , Jon Olson , Willem de Bruijn , Luigi Rizzo Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, Jun 28, 2019 at 1:06 PM Andrew Lunn wrote: > > On Fri, Jun 28, 2019 at 11:46:15AM -0700, Jakub Kicinski wrote: > > On Fri, 28 Jun 2019 10:52:27 -0700, Catherine Sullivan wrote: > > > > > +if NET_VENDOR_GOOGLE > > > > > + > > > > > +config GVE > > > > > + tristate "Google Virtual NIC (gVNIC) support" > > > > > + depends on (PCI_MSI && X86) > > > > > > > > We usually prefer for drivers not to depend on the platform unless > > > > really necessary, but IDK how that applies to the curious new world > > > > of NICs nobody can buy :) > > > > > > This is the only platform it will ever need to run on so we would really > > > prefer to not have to support others :) > > > > I think the motivation is partially to force the uniform use of generic > > APIs across the drivers, so that re-factoring of core code is easier. > > Do you have any specific pain-points in mind where x86 dependency > > simplifies things? If not I think it's a better default to not have it. > > Not a big deal, though. > > And maybe sometime in the future you might want to put this interface > in an ARM64 server? > > One 'pain-paint' is that the driver might assume cache-coherency, > which is an x86 thing. If the generic APIs have been used, it should > not be an issue, but i've not spent the time to see if the DMA API has > been used correctly. > > Andrew Mostly it is just hesitation around lack of testing. But I've done a few quick compile tests and ARM and ARM64 don't seem to have any problems so I've removed the dependency in v3.