Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760108AbcLPJni (ORCPT ); Fri, 16 Dec 2016 04:43:38 -0500 Received: from mx2.suse.de ([195.135.220.15]:39597 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754990AbcLPJnc (ORCPT ); Fri, 16 Dec 2016 04:43:32 -0500 Date: Fri, 16 Dec 2016 10:43:26 +0100 From: Borislav Petkov To: Juergen Gross Cc: Boris Ostrovsky , Linux Kernel Mailing List , xen-devel Subject: Re: Can't boot as Xen dom0 due to commit fe055896 Message-ID: <20161216094326.bnkr5a2k3njmdeyi@pd.tnic> References: <73a4d64b-b139-6579-a560-92311641d6c7@suse.com> <20161215164635.thm7ruio2ddnxszw@pd.tnic> <20161215171755.xpfuax7a6q3jofet@pd.tnic> <20161215173609.ornfok6lk5oro2pj@pd.tnic> <20161216090228.ri4alokiaagqtibt@pd.tnic> <29d252b8-67ff-bd61-f274-0ed75708cd55@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <29d252b8-67ff-bd61-f274-0ed75708cd55@suse.com> User-Agent: NeoMutt/20161014 (1.7.1) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1111 Lines: 33 On Fri, Dec 16, 2016 at 10:20:42AM +0100, Juergen Gross wrote: > Without testing, but I doubt it is working. As pv guests aren't coming > through check_loader_disabled_bsp() at all I can't see why your patch > would work for dom0. Do they go through check_loader_disabled_ap() ? > Additionally I don't think you want to call native_cpuid() if > have_cpuid_p() returns false. Good point, fixed. > So I think you want a generic "platform_allows_ucode_load()" > function checking for support of cpuid and virtualization. This > function should be called both in check_loader_disabled_bsp() and > check_loader_disabled_ap() to bail out early. See question above. If they go through check_loader_disabled_ap(), then I'm inclined to set dis_ucode_ldr to true at build time and let check_loader_disabled_bsp() set it to false on baremetal or if any of the other checks pass. If the pv guests run into check_loader_disabled_ap, then they'll see dis_ucode_ldr true and return. Ok? -- Regards/Gruss, Boris. SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg) --