Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754778AbZI3Q3g (ORCPT ); Wed, 30 Sep 2009 12:29:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754660AbZI3Q3e (ORCPT ); Wed, 30 Sep 2009 12:29:34 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:35802 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753088AbZI3Q3Z (ORCPT ); Wed, 30 Sep 2009 12:29:25 -0400 Date: Wed, 30 Sep 2009 09:27:56 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Arnd Bergmann cc: "H. Peter Anvin" , Arjan van de Ven , Roland McGrath , Sukadev Bhattiprolu , Containers , Nathan Lynch , linux-kernel@vger.kernel.org, "Eric W. Biederman" , mingo@elte.hu, Alexey Dobriyan , Pavel Emelyanov , linux-api@vger.kernel.org, kosaki.motohiro@jp.fujitsu.com Subject: Re: [RFC][v7][PATCH 8/9]: Define clone2() syscall In-Reply-To: <200909301815.45211.arnd@arndb.de> Message-ID: References: <20090924165548.GA16586@us.ibm.com> <4AC287F2.8060603@zytor.com> <200909301815.45211.arnd@arndb.de> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) 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: 856 Lines: 22 On Wed, 30 Sep 2009, Arnd Bergmann wrote: > > One more argument for this is that the new code is architecture independent > using user_stack_pointer(), while the original sys_clone is highly > architecture specific, which is a source for bugs when trying to > extend it. Umm. I don't think that is possible. You need architecture-specific code to even get access to all registers to copy and get a signal-handler-compatible stack frame. See for example arch/alpha/kernel/entry.S with the switch-stack thing etc. I don't think there is any way to make that even remotely architecture-neutral. Linus -- 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/