From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754981AbbIWMup (ORCPT ); Wed, 23 Sep 2015 08:50:45 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46353 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754483AbbIWMun (ORCPT ); Wed, 23 Sep 2015 08:50:43 -0400 Subject: Re: [PATCH] KVM: x86: fix bogus warning about reserved bits To: Borislav Petkov References: <1442910329-3357-1-git-send-email-pbonzini@redhat.com> <20150922175647.GC3568@pd.tnic> <5601C266.4060601@redhat.com> <20150923075635.GA3564@pd.tnic> <560272AF.40802@redhat.com> <20150923110733.GA3528@pd.tnic> Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org From: Paolo Bonzini Message-ID: <5602A01D.1020006@redhat.com> Date: Wed, 23 Sep 2015 14:50:37 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: <20150923110733.GA3528@pd.tnic> 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 23/09/2015 13:07, Borislav Petkov wrote: >> > + static bool first; >> > >> > best = kvm_find_cpuid_entry(vcpu, 0, 0); >> > + if (first && best) { >> > + printk("cpuid(0).ebx = %x\n", best->ebx); >> > + first = false; >> > + } else if (first) >> > + printk_ratelimited("cpuid(0) not initialized yet\n"); >> > + >> > return best && best->ebx == X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx; > Do I see it correctly that that "first" thing is never true? > > In any case, I changed it to initialize to true but still no output from > that function. > > [ 102.448438] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 4, 0xf0000000000f8) > [ 102.458706] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 3, 0xf000000000078) > [ 102.468955] walk_shadow_page_get_mmio_spte: detect reserved bits on spte, addr 0xb8000 (level 2, 0xf000000000078) Yeah, but I didn't totally need the output so I didn't bother answering with yet another v2. I'm a bit stymied and will try to find an AMD machine inside RH (it's always a pain to install latest-and-greatest kernel on unknown machines). It's probably also time to buy one too... Paolo