From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:57191) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QNkCO-0006wK-8X for qemu-devel@nongnu.org; Sat, 21 May 2011 07:18:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QNkCM-0007IA-0J for qemu-devel@nongnu.org; Sat, 21 May 2011 07:18:24 -0400 Received: from ozlabs.org ([203.10.76.45]:58505) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QNkCL-0007Hj-IP for qemu-devel@nongnu.org; Sat, 21 May 2011 07:18:21 -0400 Date: Sat, 21 May 2011 21:13:17 +1000 From: David Gibson Message-ID: <20110521111317.GC14828@yookeroo.fritz.box> References: <1305862499-12328-1-git-send-email-david@gibson.dropbear.id.au> <2C123A3E-DA94-482E-A3AD-8BC042A34BD1@web.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] Fix a bug in mtsr/mtsrin emulation on ppc64 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alexander Graf Cc: Andreas =?iso-8859-1?Q?F=E4rber?= , paulus@samba.org, qemu-devel@nongnu.org, kennethsalerno@yahoo.com On Sat, May 21, 2011 at 11:46:12AM +0200, Alexander Graf wrote: >=20 > On 21.05.2011, at 11:40, Andreas F=E4rber wrote: >=20 > > Am 20.05.2011 um 09:40 schrieb Alexander Graf: > >=20 > >> On 20.05.2011, at 05:34, David Gibson wrote: > >>=20 > >>> Early ppc64 CPUs include a hack to partially simulate the ppc32 seg= ment > >>> registers, by translating writes to them into writes to the SLB. T= his is > >>> not used by any current Linux kernel, but it is used by the openbio= s used > >>> in the qemu mac99 model. > >>>=20 > >>> Commit 81762d6dd0d430d87024f2c83e9c4dcc4329fb7d, cleaning up the SL= B > >>> handling introduced a bug in this code, breaking the openbios curre= ntly in > >>> qemu. Specifically, there was an off by one error bitshuffling the > >>> register format used by mtsr into the format needed for the SLB loa= d, > >>> causing the flag bits to end up in the wrong place. This caused th= e > >>> storage keys to be wrong under openbios, meaning that the translati= on code > >>> incorrectly thought a legitimate access was a permission violation. > >>>=20 > >>> This patch fixes the bug, at the same time it fixes some build bug = in the > >>> MMU debugging code (only exposed when DEBUG_MMU is enabled). > >>=20 > >> Thanks, applied to ppc-next :) > >=20 > > Hm. Don't you think we should split off the unrelated debug code fix = for bisecting? >=20 > Not sure if it's worth the effort. If you were bisecting before > that, you probably had DEBUG_MMU disabled anyways, because you'd > otherwise get build breakages before that specific commit anyways, > so the commit behaves as if it's only the SLB fix. Right, I don't see how the debug fixes break bisect in any way. Or least not in any way they werem't already broken. --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other= _ | _way_ _around_! http://www.ozlabs.org/~dgibson