From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754524Ab2I2M0O (ORCPT ); Sat, 29 Sep 2012 08:26:14 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36427 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754121Ab2I2M0M (ORCPT ); Sat, 29 Sep 2012 08:26:12 -0400 Message-ID: <1348921550.18878.1.camel@deadeye.wl.decadent.org.uk> Subject: Re: [ 045/262] ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores From: Ben Hutchings To: Will Deacon , Matthew Leach , Russell King Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, alan@lxorguk.ukuu.org.uk, Nicolas Pitre , Greg Kroah-Hartman Date: Sat, 29 Sep 2012 14:25:50 +0200 In-Reply-To: <20120928183003.275952918@linuxfoundation.org> References: <20120928182957.993484211@linuxfoundation.org> <20120928183003.275952918@linuxfoundation.org> Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-+CKOwOMenKE3O1ZsAYIc" X-Mailer: Evolution 3.4.3-1 Mime-Version: 1.0 X-SA-Exim-Connect-IP: 77.203.67.142 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-+CKOwOMenKE3O1ZsAYIc Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2012-09-28 at 11:49 -0700, Greg Kroah-Hartman wrote: > From: Greg KH >=20 > 3.5-stable review patch. If anyone has any objections, please let me kno= w. >=20 > ------------------ >=20 > From: Will Deacon >=20 > commit dbece45894d3ab1baac15a96dc4e1e8e23f64a93 upstream. >=20 > When enabling the MMU for ARMv7 CPUs, the decompressor does not touch > the ttbcr register, assuming that it will be zeroed (N =3D=3D 0, EAE =3D= =3D 0). > Given that only EAE is defined as 0 for non-secure copies of the > register (and a bootloader such as kexec may leave it set to 1 anyway), > we should ensure that we reset the register ourselves before turning on > the MMU. >=20 > This patch zeroes TTBCR.EAE and TTBCR.N prior to enabling the MMU for > ARMv7 cores in the decompressor, configuring us exclusively for 32-bit > translation tables via TTBR0. >=20 > Acked-by: Nicolas Pitre > Signed-off-by: Matthew Leach > Signed-off-by: Will Deacon > Signed-off-by: Russell King > Signed-off-by: Greg Kroah-Hartman [...] Is this also needed for earlier kernel versions? If so, can you provide a backported version? Ben. --=20 Ben Hutchings Usenet is essentially a HUGE group of people passing notes in class. - Rachel Kadel, `A Quick Guide to Newsgroup Etiquette= ' --=-+CKOwOMenKE3O1ZsAYIc Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIVAwUAUGbozue/yOyVhhEJAQr9rxAAj4+A53Rp9E+DlMe9Pu/xNmJWTUXWRLx3 xUVyrUsNyzk8U9OYxBsZ/mjP1WzwOzNUFDyG5BjvmCh5L30w4knrZK8p1ehrvXpr ekihw2VNFwXjCmE1T/gFnosXNClAFjoi14j/PIoSd2u7NQJWiWpxYz45uBGclqmh TxHJSEUVBIalThcPiKtktxgk35BtVURr5hqg/ZCafxcbakGwQUQ1aV47yrd300lh L95KqaTp8eaMX+f5s7XJcWfsMAamgY1jLxX+gfxajooecleypBnZ57OmsVLU6Tz3 el7DYNfL+suTbyVl06orOdNJ8JejxBN5BMlOAF1IFo0Uo7LpwntIG5NU4yMy7ckL RabGQGxEWGS7HMRLmYC6s3I9cCgKsdouW5/IspOEfhoWREKUygP9iNSVl+t525Ej l73Kmo+bYDEE88JOAQY0EPMldFiOxRJV/vLELcs/bC0EOEvlAa/nP7s36b2X7mND /X7BKLkmZwdXZ938OEmjgHvpw5SdXXkC/2Ax2u8soiXkCbHPgsEfIA8f4jVX2NY+ V4pqaWi9OjhNABGGlSpSoWItTG8QPtOKIw6RgJEIb/U2f943MBXaJX3QtpxLRj2t 1iRUo9nLv8xwFCYYmlTdA/YNjyzSh1EDROG8cVD2jRsOgjCcX8y5UL/ZtoG/9Pzn JNIeC8yc5ng= =wu/2 -----END PGP SIGNATURE----- --=-+CKOwOMenKE3O1ZsAYIc--