Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755798AbYF3AEU (ORCPT ); Sun, 29 Jun 2008 20:04:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753162AbYF3AEN (ORCPT ); Sun, 29 Jun 2008 20:04:13 -0400 Received: from mail.tmr.com ([64.65.253.246]:46054 "EHLO gaimboi.tmr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753062AbYF3AEM (ORCPT ); Sun, 29 Jun 2008 20:04:12 -0400 Message-ID: <486823CB.8050603@tmr.com> Date: Sun, 29 Jun 2008 20:07:39 -0400 From: Bill Davidsen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.0.8) Gecko/20061105 SeaMonkey/1.0.6 MIME-Version: 1.0 To: Roland McGrath CC: Jeremy Fitzhardinge , Linux Kernel Mailing List Subject: Re: Various x86 syscall mechanisms References: <485C2875.2050204@goop.org> <20080627204954.166D0154077@magilla.localdomain> In-Reply-To: <20080627204954.166D0154077@magilla.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1124 Lines: 26 Roland McGrath wrote: >> As far as I can work out, an x86_32 kernel will use "int 0x80" and >> "sysenter" for system calls. 64-bit kernel will use just "syscall" for >> 64-bit processes (though you can use "int 0x80" to access the 32-bit >> syscall interface from a 64-bit process), but will allow "sysenter", >> "syscall" or "int 0x80" for 32-on-64 processes. > > That is correct, with the caveats below. > Thanks for setting this out clearly, I've seen most of it (from Andi, I think) in bits, and one of the scheduler folk had a comment relevant to scheduling which I can't find now, but this is both technical and historical, and thus a nice thing to hand to someone with a related question. Well done. -- Bill Davidsen "We have more to fear from the bungling of the incompetent than from the machinations of the wicked." - from Slashdot -- 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/