From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754000AbaCGWMd (ORCPT ); Fri, 7 Mar 2014 17:12:33 -0500 Received: from mga09.intel.com ([134.134.136.24]:54695 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751945AbaCGWMc (ORCPT ); Fri, 7 Mar 2014 17:12:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,610,1389772800"; d="scan'208";a="488190157" Message-ID: <531A4426.30504@linux.intel.com> Date: Fri, 07 Mar 2014 14:11:50 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: Dave Jones , Borislav Petkov , Fengguang Wu , Ingo Molnar , Yinghai Lu , LKML , Paolo Bonzini Subject: Re: [qemu64,+smep,+smap] WARNING: CPU: 1 PID: 0 at arch/x86/kernel/cpu/amd.c:220 init_amd() References: <20140307015833.GA10048@localhost> <53195336.9080606@linux.intel.com> <20140307055035.GA5230@localhost> <531A164B.8040402@linux.intel.com> <20140307191050.GA10961@redhat.com> <531A33A2.5030706@linux.intel.com> <20140307213856.GF5255@pd.tnic> <20140307220655.GA580@redhat.com> In-Reply-To: <20140307220655.GA580@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/07/2014 02:06 PM, Dave Jones wrote: > On Fri, Mar 07, 2014 at 10:38:56PM +0100, Borislav Petkov wrote: > > > * Another option would be if we change the f/m/s of "qemu64" so that > > the test doesn't fire. > > > > What also makes me wonder is why is this thing even called qemu64?? AMD > > family 6 was 32-bit only CPUs so 64 is kinda wrong IMO. I mean, the > > kernel code is in "ifdef CONFIG_X86_32" block so "qemu64" is patently > > wrong naming. > > Additionally, fam:6 model:6 stepping 3 never existed in the real world afaict. > I used to keep x86info's stepping db pretty up to date, and that only has knowledge > of stepping 1 & 2.[*] Modelling qemu on something from the real world might be > a better idea than inventing new special cases. > > > Oh, and the thing has CPUID_EXT2_LM which is also a WTH moment for me. > > Paolo, what's going on here? > > Yeah, this is a mess, there should be no family < 0xf with LM set. > > Dave For AMD, at least. Intel obviously have a bunch of chips with family == 6 and LM. Perhaps Fengguang should switch from "qemu64,+smep,+smap" to something like "Haswell,+smep,+smap" instead for the time being at least? -hpa