Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762519AbZAONWa (ORCPT ); Thu, 15 Jan 2009 08:22:30 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755220AbZAONWW (ORCPT ); Thu, 15 Jan 2009 08:22:22 -0500 Received: from ftp.linux-mips.org ([213.58.128.207]:51503 "EHLO ftp.linux-mips.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754705AbZAONWW (ORCPT ); Thu, 15 Jan 2009 08:22:22 -0500 Date: Thu, 15 Jan 2009 13:22:14 +0000 (GMT) From: "Maciej W. Rozycki" To: Jan-Benedict Glaw cc: Ingo Molnar , Alan Cox , Peter Zijlstra , Jiri Kosina , Adam Osuchowski , linux-kernel@vger.kernel.org, Nick Piggin , Thomas Gleixner , "H. Peter Anvin" Subject: Re: Is 386 processor still supported? In-Reply-To: <20090115123614.GR11087@lug-owl.de> Message-ID: References: <20090108120338.6b8b4567@zonk.pl> <1231424025.11687.447.camel@twins> <1231424833.11687.452.camel@twins> <20090108150448.2393aeb0@lxorguk.ukuu.org.uk> <20090108151046.GK18120@elte.hu> <20090115123614.GR11087@lug-owl.de> User-Agent: Alpine 1.10 (LFD 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1088 Lines: 24 On Thu, 15 Jan 2009, Jan-Benedict Glaw wrote: > * Debian's baseline libc is compiled to use LOCK and some other > newish instructions that are not available on a real i386 CPU. LOCK dates back to the 8086 -- it has to work with the i386. What is not supported are the following i486 additions: CMPXCHG (amusingly enough early i486 steppings used a different opcode for this one; no idea if it is still possible to find such a CPU), XADD and BSWAP, the latter being fairly unimportant. > * There was a patch flying around to introduce a kernel-based > emulator for those instructions. However, this was (at that time) > neither included in Debian's kernel, nor in the upstream sources. UP emulation of CMPXCHG and XADD for userland should be rather trivial, so why not include it like with LL/SC for MIPS? Maciej -- 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/