From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:34513) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bEtw2-0003LG-IS for qemu-devel@nongnu.org; Mon, 20 Jun 2016 03:47:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bEtvx-0003sD-Hu for qemu-devel@nongnu.org; Mon, 20 Jun 2016 03:47:54 -0400 References: <576392B1.6030204@kaod.org> <5763A258.2010408@redhat.com> <5763D3EF.6060305@kaod.org> <5763D8D1.70701@redhat.com> <3258f4f3-6f5d-bb1f-9cac-2d19cac7ab53@kaod.org> <1466292910.24271.95.camel@kernel.crashing.org> <1ecfdda6-49a9-a737-80fd-a229c5a1fcf1@kaod.org> <1466345334.24271.123.camel@kernel.crashing.org> <3a87a63c-4c9e-354e-e089-dadfd00b4885@kaod.org> <1466370758.24271.125.camel@kernel.crashing.org> <20160620021902.GF6858@voom.fritz.box> <33ad19a4-0940-a6ad-9545-a20218453ec8@kaod.org> From: Thomas Huth Message-ID: <57679FA0.1050709@redhat.com> Date: Mon, 20 Jun 2016 09:47:44 +0200 MIME-Version: 1.0 In-Reply-To: <33ad19a4-0940-a6ad-9545-a20218453ec8@kaod.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [Qemu-ppc] [PATCH 01/10] ppc: Fix rfi/rfid/hrfi/... emulation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= , David Gibson , Benjamin Herrenschmidt Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org On 20.06.2016 08:17, C=C3=A9dric Le Goater wrote: > On 06/20/2016 04:19 AM, David Gibson wrote: >> On Mon, Jun 20, 2016 at 07:12:38AM +1000, Benjamin Herrenschmidt wrote= : >>> On Sun, 2016-06-19 at 19:23 +0200, C=C3=A9dric Le Goater wrote: >>>>> You can run a 32-bit OS or firmware on ppc64, but it needs to know = that >>>>> it's running on a 64-bit chip and do a few things differently. >>>> >>>> yes sure but qemu would still allow rfi under 64bit CPUs, that is wh= at=20 >>>> I was concerned about. Is that ok ?=20 >>> >>> Why ? A real CPU won't allow it, why should we ? >> >> We shouldn't. However, I'm inclined to in for now, until we have an >> OpenBIOS fix actually committed. I'd prefer to keep the existing >> setup sorta-working when the current situation is unlikely to break >> working code, even though it's definitely wrong. >> >> BenH or C=C3=A9dric, if you want to resend the hrfi fix patch with the >> 64-bit rfi support left in for no, that would be good. >=20 > The current patch does not need fixing. I will send the OpenBIOS patch=20 > shortly after I have looked at the FPU exception. >=20 > Linux ppc behaves the same on a 970. So we will need to fix the 'rfi's > there also.=20 Really? Wow, that surprises me. That OpenBIOS code likely never ran on a real 970 hardware, so that's not too much surprising that the "rfi" sneaked in there, but the Linux kernel certainly ran on a real 970 once, so I wonder why it's not properly using rfid for the 970 yet? Thomas