Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755093Ab1BMVRY (ORCPT ); Sun, 13 Feb 2011 16:17:24 -0500 Received: from terminus.zytor.com ([198.137.202.10]:56595 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754952Ab1BMVRS (ORCPT ); Sun, 13 Feb 2011 16:17:18 -0500 Message-ID: <4D584A49.80306@zytor.com> Date: Sun, 13 Feb 2011 13:16:57 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Thunderbird/3.1.7 MIME-Version: 1.0 To: x32-abi@googlegroups.com CC: "H.J. Lu" , Arnd Bergmann , GCC Development , GNU C Library , LKML , "H. Peter Anvin" Subject: Re: X32 psABI status References: <201102132110.29630.arnd@arndb.de> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1624 Lines: 41 On 02/13/2011 01:10 PM, H.J. Lu wrote: >>> >>> 1. Kernel interface with syscall is close to be finalized. >> I don't think calling it "finalized" is accurate... it is more accurately described as "prototyped". >> Really? I haven't seen this being posted for review yet ;-) >> >> The basic concept looks entirely reasonable to me, but I'm >> curious what drove the decision to start out with the x86_64 >> system calls instead of the generic ones. >> >> Since tile was merged, we now have support for compat syscalls >> in the generic syscall ABI. I would have assumed that it >> was possible to just use those if you decide to do a new >> ABI in the first place. >> >> The other option that would have appeared natural to me is >> to just use the existing 32 bit compat ABI with the few >> necessary changes done based on the personality. The actual idea is to use the i386 compat ABI for memory layout, but with a 64-bit register convention. That means that system calls that don't make references to memory structures can simply use the 64-bit system calls, otherwise we're planning to reuse the i386 compat system calls, but invoke them via the syscall instruction (which requires a new system call table) and to pass 64-bit arguments in single registers. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/