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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 B31DEC4338F for ; Thu, 19 Aug 2021 21:58:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 947306109E for ; Thu, 19 Aug 2021 21:58:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235923AbhHSV6o convert rfc822-to-8bit (ORCPT ); Thu, 19 Aug 2021 17:58:44 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.85.151]:37977 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235771AbhHSV6n (ORCPT ); Thu, 19 Aug 2021 17:58:43 -0400 Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-222-K8o7LF4xO6exf4bKEugwaw-1; Thu, 19 Aug 2021 22:58:04 +0100 X-MC-Unique: K8o7LF4xO6exf4bKEugwaw-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) by AcuMS.aculab.com (fd9f:af1c:a25b:0:994c:f5c2:35d6:9b65) with Microsoft SMTP Server (TLS) id 15.0.1497.23; Thu, 19 Aug 2021 22:58:03 +0100 Received: from AcuMS.Aculab.com ([fe80::994c:f5c2:35d6:9b65]) by AcuMS.aculab.com ([fe80::994c:f5c2:35d6:9b65%12]) with mapi id 15.00.1497.023; Thu, 19 Aug 2021 22:58:03 +0100 From: David Laight To: 'Christoph Hellwig' , "torvic9@mailbox.org" CC: "linux-kernel@vger.kernel.org" , "x86@kernel.org" , "clang-built-linux@googlegroups.com" , "graysky@archlinux.us" Subject: RE: [PATCH 2/2] x86, Makefile: Add new generic x86-64 settings v2/v3/v4 Thread-Topic: [PATCH 2/2] x86, Makefile: Add new generic x86-64 settings v2/v3/v4 Thread-Index: AQHXlAD0agS+R5TrUku3Pq8hTf8Ltqt7Yd3A Date: Thu, 19 Aug 2021 21:58:03 +0000 Message-ID: References: <269701460.117528.1629210189833@office.mailbox.org> <796036867.117557.1629210288168@office.mailbox.org> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christoph Hellwig > Sent: 18 August 2021 08:15 > > On Tue, Aug 17, 2021 at 04:24:48PM +0200, torvic9@mailbox.org wrote: > > + Generic x86-64 CPU. > > + Run equally well on all x86-64 CPUs with min support of x86-64-v2. > > > + help > > + Generic x86-64-v3 CPU with v3 instructions. > > + Run equally well on all x86-64 CPUs with min support of x86-64-v3. > > + > > > + help > > + Generic x86-64 CPU with v4 instructions. > > + Run equally well on all x86-64 CPUs with min support of x86-64-v4. > > How the f&%$% is a user supposed to know what these garbage descriptions > are supposed to mean? My thoughts. I then looked up the link. Most of the extra instructions are the AVX related ones. They better not get enabled for a kernel build at all. I wish I knew whether 'no-avx' actually implied 'no-avx2' and all later avx options? Or do kernel builds have to spot each new option and disable in in turn? David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)