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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 8ADE9C0044C for ; Mon, 5 Nov 2018 08:52:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4621D20819 for ; Mon, 5 Nov 2018 08:52:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="D8MLgKNL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4621D20819 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arndb.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727615AbeKESLb (ORCPT ); Mon, 5 Nov 2018 13:11:31 -0500 Received: from mail-qk1-f196.google.com ([209.85.222.196]:36318 "EHLO mail-qk1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726125AbeKESLb (ORCPT ); Mon, 5 Nov 2018 13:11:31 -0500 Received: by mail-qk1-f196.google.com with SMTP id o125so13336850qkf.3 for ; Mon, 05 Nov 2018 00:52:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc:content-transfer-encoding; bh=8JMYtjfNYxLfbYDC9OvzWnhNZN5UoKOiwiG13yTWbTE=; b=D8MLgKNLezWGWd7LOpCrLZDP5Nr+JaEOE7X6Xqbg2a/Eyh46nZ1ApM2bDPcFC3jwKr XPt7RrF8cp36pkH/mtNlUvElB/ak5HyiC9RQm6aZ9mkll9yyotYT1K/xQ9+lvfPFEWSX 9a+4CRE9k+tOnrLIPPZhBtdpWh3dithgTisXhwlwjd9GiI7aPvroqnx2lQTvcN9Ck3JP KqONQ/EGDrV0nCtKR6Z7miCULypvSDozUxVGqtTddwe2ORpuLbJUqu7Maanuz7OAGPhi kx7l7AmiCNXpCY1bMZHhns8Ri45Yeu2OZuLBQ/p4UNTmJphtKahAtJX4/1g74VHtel7x X7nQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc:content-transfer-encoding; bh=8JMYtjfNYxLfbYDC9OvzWnhNZN5UoKOiwiG13yTWbTE=; b=TWufWhcpdG7gxPuTW1TiGypGAFkjZoaSDRAnoY5aENxUP2GEMqX9sps6vOzfyv8Dlm G+2joPtHlrHzn8BrOg3kKl2RjM+P9d/ZY/2PPXaID7Fr0sIPupWkR5gt1cPhmvxXY4HE X2U4Lr+U4gjiFyZPvgqKQnMgLkQtkKvRg5sdFNK3JBmO/sR9jrgDfohUU2H94uKymNDc 35Ap2W84a/NZNq87l5YJnBqwt0cNNuFqAcXMJH3rgiowUXK9Us/iS+Kp8FnrkiXB7ED0 YjgqUC1vwNhyt+IJ5fhuQItqppjmUWpckEP9S0U9IM702k1opmPYniLYRmveeGHyQWyg RSJA== X-Gm-Message-State: AGRZ1gLqH0oBBAZv9tHqiHfORNuGVCMkwUIEDnVh5tpCKg0TmkJKewhF QBvASzXlIi36MRnGg4vowLQ67B0eGzLAQLNIdHo= X-Google-Smtp-Source: AJdET5dLcTAkwp9cARYapZYvWFyATrmLu/B6uVtF7HO3WXgZlcFDLisAuDY3POGB3YUMnu9iMatiKZiE/Va4je2jxWQ= X-Received: by 2002:a37:a3c6:: with SMTP id m189mr19797249qke.173.1541407973298; Mon, 05 Nov 2018 00:52:53 -0800 (PST) MIME-Version: 1.0 Received: by 2002:a0c:9881:0:0:0:0:0 with HTTP; Mon, 5 Nov 2018 00:52:52 -0800 (PST) In-Reply-To: <20181105070551.GA7274@infradead.org> References: <20181101174857.du2zu4vnrhpu5asf@excalibur.cnev.de> <20181105065807.GA1286@andestech.com> <20181105070551.GA7274@infradead.org> From: Arnd Bergmann Date: Mon, 5 Nov 2018 09:52:52 +0100 X-Google-Sender-Auth: o-kIcVGL0PLGM20_dbB_NR5HFxM Message-ID: Subject: Re: [RFC 0/2] RISC-V: A proposal to add vendor-specific code To: Christoph Hellwig Cc: Vincent Chen , aou@eecs.berkeley.edu, alankao@andestech.com, greentime@andestech.com, palmer@sifive.com, linux-kernel@vger.kernel.org, zong@andestech.com, kito@andestech.com, linux-riscv@lists.infradead.org, deanbo422@gmail.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/5/18, Christoph Hellwig wrote: > On Mon, Nov 05, 2018 at 02:58:07PM +0800, Vincent Chen wrote: >> Many thanks for kinds of comments. I quickly synthesize the comments and >> list them as below. >> 1. The kernel image shall include all vendor-specific code. > > I fundamentally disagree with this=E2=80=A6 and think it should be the co= ntrary. > > 1. The kernel shall support no vendor specific instructions whatsoever, > period. I think what was meant above is 1. If a vendor extension requires kernel support, that support must be able to be built into a kernel image without breaking support for CPUs that do not have that extension, to allow building a single kernel image that works on all CPUs. Arnd