From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758107Ab2ARVBp (ORCPT ); Wed, 18 Jan 2012 16:01:45 -0500 Received: from mail-ww0-f44.google.com ([74.125.82.44]:53250 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753501Ab2ARVBn (ORCPT ); Wed, 18 Jan 2012 16:01:43 -0500 MIME-Version: 1.0 In-Reply-To: <4F1731C1.4050007@zytor.com> References: <20120116183730.GB21112@redhat.com> <20120117164523.GA17070@redhat.com> <20120117170512.GB17070@redhat.com> <49017bd7edab7010cd9ac767e39d99e4.squirrel@webmail.greenhost.nl> <20120118015013.GR11715@one.firstfloor.org> <20120118020453.GL7180@jl-vm1.vm.bytemark.co.uk> <20120118022217.GS11715@one.firstfloor.org> <4F1731C1.4050007@zytor.com> From: Linus Torvalds Date: Wed, 18 Jan 2012 13:01:20 -0800 X-Google-Sender-Auth: zwGrQMZPRJQOj4wVPzhyPYMuzC4 Message-ID: Subject: Re: Compat 32-bit syscall entry from 64-bit task!? To: "H. Peter Anvin" Cc: Indan Zupancic , Andi Kleen , Jamie Lokier , Andrew Lutomirski , Oleg Nesterov , Will Drewry , linux-kernel@vger.kernel.org, keescook@chromium.org, john.johansen@canonical.com, serge.hallyn@canonical.com, coreyb@linux.vnet.ibm.com, pmoore@redhat.com, eparis@redhat.com, djm@mindrot.org, segoon@openwall.com, rostedt@goodmis.org, jmorris@namei.org, scarybeasts@gmail.com, avi@redhat.com, penberg@cs.helsinki.fi, viro@zeniv.linux.org.uk, mingo@elte.hu, akpm@linux-foundation.org, khilman@ti.com, borislav.petkov@amd.com, amwang@redhat.com, ak@linux.intel.com, eric.dumazet@gmail.com, gregkh@suse.de, dhowells@redhat.com, daniel.lezcano@free.fr, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, olofj@chromium.org, mhalcrow@google.com, dlaor@redhat.com, Roland McGrath Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 18, 2012 at 12:55 PM, H. Peter Anvin wrote: > > If we're going to use bits in an existing register field I would be > happier if we used bits [31:16] of CS, which are unlikely to ever be > used for anything. See my note about that: I would have preferred CS or ORIG_AX myself, but that breaks existing binaries. So that isn't really an option. Linus From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: Compat 32-bit syscall entry from 64-bit task!? Date: Wed, 18 Jan 2012 13:01:20 -0800 Message-ID: References: <20120116183730.GB21112@redhat.com> <20120117164523.GA17070@redhat.com> <20120117170512.GB17070@redhat.com> <49017bd7edab7010cd9ac767e39d99e4.squirrel@webmail.greenhost.nl> <20120118015013.GR11715@one.firstfloor.org> <20120118020453.GL7180@jl-vm1.vm.bytemark.co.uk> <20120118022217.GS11715@one.firstfloor.org> <4F1731C1.4050007@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Cc: Indan Zupancic , Andi Kleen , Jamie Lokier , Andrew Lutomirski , Oleg Nesterov , Will Drewry , linux-kernel@vger.kernel.org, keescook@chromium.org, john.johansen@canonical.com, serge.hallyn@canonical.com, coreyb@linux.vnet.ibm.com, pmoore@redhat.com, eparis@redhat.com, djm@mindrot.org, segoon@openwall.com, rostedt@goodmis.org, jmorris@namei.org, scarybeasts@gmail.com, avi@redhat.com, penberg@cs.helsinki.fi, viro@zeniv.linux.org.uk, mingo@elte.hu, akpm@linux-foundation.org, khilman@ti.com, borislav.petkov@amd.com, amwang@redhat.com, ak@linux.intel.com, eric.dumazet@gmail.com, gregkh@suse.de, dhowells@redhat.com, daniel.lezcano@free.fr, linux-fsdevel@vger.kernel.org, linux-security-module@vger.kernel.org, olofj@chromium.org, mhalcrow@google.com, dlaor@redhat.com, Ro To: "H. Peter Anvin" Return-path: In-Reply-To: <4F1731C1.4050007@zytor.com> Sender: linux-security-module-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, Jan 18, 2012 at 12:55 PM, H. Peter Anvin wrote: > > If we're going to use bits in an existing register field I would be > happier if we used bits [31:16] of CS, which are unlikely to ever be > used for anything. See my note about that: I would have preferred CS or ORIG_AX myself, but that breaks existing binaries. So that isn't really an option. Linus