Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752634AbZIKLHF (ORCPT ); Fri, 11 Sep 2009 07:07:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752160AbZIKLHE (ORCPT ); Fri, 11 Sep 2009 07:07:04 -0400 Received: from bohort.kerlabs.com ([62.160.40.57]:37817 "EHLO bohort.kerlabs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751612AbZIKLHD (ORCPT ); Fri, 11 Sep 2009 07:07:03 -0400 X-Greylist: delayed 367 seconds by postgrey-1.27 at vger.kernel.org; Fri, 11 Sep 2009 07:07:03 EDT Date: Fri, 11 Sep 2009 13:00:56 +0200 From: Louis Rilling To: Arnd Bergmann Cc: Sukadev Bhattiprolu , Containers , Nathan Lynch , linux-kernel@vger.kernel.org, "Eric W. Biederman" , hpa@zytor.com, mingo@elte.hu, torvalds@linux-foundation.org, Alexey Dobriyan , Pavel Emelyanov Subject: Re: [RFC][v6][PATCH 8/9]: Define clone_with_pids() syscall Message-ID: <20090911110056.GA12824@hawkmoon.kerlabs.com> Mail-Followup-To: Arnd Bergmann , Sukadev Bhattiprolu , Containers , Nathan Lynch , linux-kernel@vger.kernel.org, "Eric W. Biederman" , hpa@zytor.com, mingo@elte.hu, torvalds@linux-foundation.org, Alexey Dobriyan , Pavel Emelyanov References: <20090910060627.GA24343@us.ibm.com> <200909100931.25585.arnd@arndb.de> <20090910212837.GA31459@us.ibm.com> <200909111231.30495.arnd@arndb.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=_bohort-29211-1252666815-0001-2" Content-Disposition: inline In-Reply-To: <200909111231.30495.arnd@arndb.de> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1873 Lines: 57 This is a MIME-formatted message. If you see this text it means that your E-mail software does not support MIME-formatted messages. --=_bohort-29211-1252666815-0001-2 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 11/09/09 12:31 +0200, Arnd Bergmann wrote: > On Thursday 10 September 2009, Sukadev Bhattiprolu wrote: > > Since this is a variant of clone() and clone is listed as a PTREGSCALL(= ), > > I pass in the pt_regs. > >=20 > > arch/x86/kernel/entry_32.S lists clone() under this comment: > >=20 > > /* > > * System calls that need a pt_regs pointer. > > */ > >=20 > > Is there a guideline on what system calls use/need pt_regs ? >=20 > You need pt_regs if you access any registers from the user task > other than the argument registers. In case of clone(), this is > the user stack pointer. AFAICS clone() actually needs _all_ registers (see x86 copy_thread() for instance). Any variant of clone() will have this requirement. Louis --=20 Dr Louis Rilling Kerlabs Skype: louis.rilling Batiment Germanium Phone: (+33|0) 6 80 89 08 23 80 avenue des Buttes de Coesmes http://www.kerlabs.com/ 35700 Rennes --=_bohort-29211-1252666815-0001-2 Content-Type: application/pgp-signature; name="signature.asc" Content-Transfer-Encoding: 7bit Content-Description: Digital signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkqqLegACgkQVKcRuvQ9Q1TSUQCguOM4SiZDaN6vYaxukoMfnggt xCEAn0ixmZQL/6PoIqEMqLO7lyn+9sBE =QGGS -----END PGP SIGNATURE----- --=_bohort-29211-1252666815-0001-2-- -- 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/