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=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 65890C4321A for ; Fri, 28 Jun 2019 20:06:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 380932086D for ; Fri, 28 Jun 2019 20:06:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="F9Qu5N2A" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727070AbfF1UGa (ORCPT ); Fri, 28 Jun 2019 16:06:30 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:41734 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726809AbfF1UGa (ORCPT ); Fri, 28 Jun 2019 16:06:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=eFxYurngNB9thjDjZoKv0CgvUoLipNFN9ma3HIqZbB4=; b=F9Qu5N2ASGv7+O8j2PJ+rh2huC wlAIIONViKJsz8QoJr5+xojsQzcYONKjmTjrgKhBLedQgOFdXw2wqokTxITISf7L0WYvd43i8DeNL M1MyONOZZz2lozOk2NVaJ3/KKZVGo1dLPofmilwwTBoLLOviieazpQ2Z1S5//aeFkykI=; Received: from andrew by vps0.lunn.ch with local (Exim 4.89) (envelope-from ) id 1hgx8e-0001Fu-Ia; Fri, 28 Jun 2019 22:06:28 +0200 Date: Fri, 28 Jun 2019 22:06:28 +0200 From: Andrew Lunn To: Jakub Kicinski Cc: Catherine Sullivan , netdev@vger.kernel.org, Sagi Shahar , Jon Olson , Willem de Bruijn , Luigi Rizzo Subject: Re: [net-next 1/4] gve: Add basic driver framework for Compute Engine Virtual NIC Message-ID: <20190628200628.GS27733@lunn.ch> References: <20190626185251.205687-1-csully@google.com> <20190626185251.205687-2-csully@google.com> <20190626160832.3f191a53@cakuba.netronome.com> <20190628114615.4fc81791@cakuba.netronome.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190628114615.4fc81791@cakuba.netronome.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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