Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752727AbcLHJOA (ORCPT ); Thu, 8 Dec 2016 04:14:00 -0500 Received: from mail.skyhub.de ([78.46.96.112]:41390 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751631AbcLHJN4 (ORCPT ); Thu, 8 Dec 2016 04:13:56 -0500 Date: Thu, 8 Dec 2016 10:13:47 +0100 From: Borislav Petkov To: Thomas Gleixner Cc: LKML , x86@kernel.org, Peter Zijlstra , "Charles (Chas) Williams" , "M. Vefa Bicakci" , Alok Kataria , Boris Ostrovsky Subject: Re: [PATCH] x86/smpboot: Make logical package management more robust Message-ID: <20161208091346.uzz3ix4hfpvx2bfu@pd.tnic> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: 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: 1633 Lines: 41 On Thu, Dec 08, 2016 at 10:04:25AM +0100, Thomas Gleixner wrote: > The logical package management has several issues: > > - The APIC ids provided by ACPI are not required to be the same as the > initial APIC id which can be retrieved by CPUID. The APIC ids provided > by ACPI are those which are written by the BIOS into the APIC. The > initial id is set by hardware and can not be changed. The hardware > provided ids contain the real hardware package information. > > Especially AMD sets the effective APIC id different from the hardware id > as they need to reserve space for the IOAPIC ids starting at id 0. > > As a consequence those machines trigger the currently active firmware > bug printouts in dmesg, These are obviously wrong. > > - Virtual machines have their own interesting way of enumerating APICs and > packages which are not reliably covered by the current implementation. > > The sizing of the mapping array has been tweaked to be generously large to > handle systems which provide a wrong core count when HT is disabled so the > whole magic which checks for space in the physical hotplug case is not > needed anymore. > > Simplify the whole machinery and do the mapping when the CPU starts and the > CPUID derived physical package information is available. This solves the > observed problems on AMD machines and works for the virtualization issues > as well. > > Signed-off-by: Thomas Gleixner Already Tested-by: Borislav Petkov Thanks! -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.