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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 34E83C3A5A7 for ; Mon, 2 Sep 2019 13:01:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1861E2168B for ; Mon, 2 Sep 2019 13:01:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729930AbfIBNBb (ORCPT ); Mon, 2 Sep 2019 09:01:31 -0400 Received: from gate.crashing.org ([63.228.1.57]:53196 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729770AbfIBNBa (ORCPT ); Mon, 2 Sep 2019 09:01:30 -0400 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id x82D0CbT029470; Mon, 2 Sep 2019 08:00:12 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id x82D09fF029469; Mon, 2 Sep 2019 08:00:09 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Mon, 2 Sep 2019 08:00:08 -0500 From: Segher Boessenkool To: Michael Ellerman Cc: Michal Suchanek , linuxppc-dev@lists.ozlabs.org, Benjamin Herrenschmidt , Paul Mackerras , Alexander Viro , Nicholas Piggin , Christophe Leroy , Breno Leitao , Arnd Bergmann , Heiko Carstens , Greg Kroah-Hartman , Firoz Khan , Thomas Gleixner , Joel Stanley , Hari Bathini , Michael Neuling , Andrew Donnellan , Russell Currey , Diana Craciun , "Eric W. Biederman" , David Hildenbrand , Allison Randal , Andrew Morton , Madhavan Srinivasan , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH v7 5/6] powerpc/64: Make COMPAT user-selectable disabled on littleendian by default. Message-ID: <20190902130008.GZ31406@gate.crashing.org> References: <87ftlftpy7.fsf@mpe.ellerman.id.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87ftlftpy7.fsf@mpe.ellerman.id.au> User-Agent: Mutt/1.4.2.3i Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 02, 2019 at 12:03:12PM +1000, Michael Ellerman wrote: > Michal Suchanek writes: > > On bigendian ppc64 it is common to have 32bit legacy binaries but much > > less so on littleendian. > > I think the toolchain people will tell you that there is no 32-bit > little endian ABI defined at all, if anything works it's by accident. There of course is a lot of powerpcle-* support. The ABI used for it on linux is the SYSV ABI, just like on BE 32-bit. There also is specific powerpcle-linux support in GCC, and in binutils, too. Also, config.guess/config.sub supports it. Half a year ago this all built fine (no, I don't test it often either). I don't think glibc supports it though, so I wonder if anyone builds an actual system with it? Maybe busybox or the like? > So I think we should not make this selectable, unless someone puts their > hand up to say they want it and are willing to test it and keep it > working. What about actual 32-bit LE systems? Does anyone still use those? Segher