From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756293AbcJGIFJ (ORCPT ); Fri, 7 Oct 2016 04:05:09 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:43254 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756270AbcJGIE4 (ORCPT ); Fri, 7 Oct 2016 04:04:56 -0400 Date: Fri, 7 Oct 2016 10:02:23 +0200 (CEST) From: Thomas Gleixner To: Jiri Olsa cc: Prarit Bhargava , linux-kernel@vger.kernel.org, Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, Peter Zijlstra , Len Brown , Borislav Petkov , Andi Kleen , Juergen Gross , dyoung@redhat.com, Eric Biederman , kexec@lists.infradead.org Subject: Re: [PATCH] arch/x86: Fix kdump on x86 with physically hotadded CPUs In-Reply-To: <20161007064927.GA2200@krava> Message-ID: References: <1475514432-27682-1-git-send-email-prarit@redhat.com> <57F39C09.10001@redhat.com> <20161005161455.GA26029@krava> <57F66CF7.7040204@redhat.com> <20161007064927.GA2200@krava> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 7 Oct 2016, Jiri Olsa wrote: > On Thu, Oct 06, 2016 at 11:25:43AM -0400, Prarit Bhargava wrote: > > I thought about doing this but it seems like every time some driver uses > > topology_logical_package_id() the driver would have to replicate the error > > checking code. > > hm, unless we guarantee topology_logical_package_id always > returns sane values I dont see another way I did some deeper investigation. So with prarits patch there is only one possibility left to end up with an empty package id: SMP Kernel on UP Machine, which has neither ACPI nor MADT. But those machines are not a problem because they don't use any drivers which would make use of it. Aside of that for UP we just can set the node of the cpu to 0 and be done with it. I'll pick up Prarits patch and amend it. Thanks, tglx From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galois.linutronix.de ([2a01:7a0:2:106d:700::1]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bsQAl-00086I-57 for kexec@lists.infradead.org; Fri, 07 Oct 2016 08:06:29 +0000 Date: Fri, 7 Oct 2016 10:02:23 +0200 (CEST) From: Thomas Gleixner Subject: Re: [PATCH] arch/x86: Fix kdump on x86 with physically hotadded CPUs In-Reply-To: <20161007064927.GA2200@krava> Message-ID: References: <1475514432-27682-1-git-send-email-prarit@redhat.com> <57F39C09.10001@redhat.com> <20161005161455.GA26029@krava> <57F66CF7.7040204@redhat.com> <20161007064927.GA2200@krava> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: Jiri Olsa Cc: Prarit Bhargava , Len Brown , Andi Kleen , Juergen Gross , Peter Zijlstra , x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Ingo Molnar , Eric Biederman , "H. Peter Anvin" , Borislav Petkov , dyoung@redhat.com On Fri, 7 Oct 2016, Jiri Olsa wrote: > On Thu, Oct 06, 2016 at 11:25:43AM -0400, Prarit Bhargava wrote: > > I thought about doing this but it seems like every time some driver uses > > topology_logical_package_id() the driver would have to replicate the error > > checking code. > > hm, unless we guarantee topology_logical_package_id always > returns sane values I dont see another way I did some deeper investigation. So with prarits patch there is only one possibility left to end up with an empty package id: SMP Kernel on UP Machine, which has neither ACPI nor MADT. But those machines are not a problem because they don't use any drivers which would make use of it. Aside of that for UP we just can set the node of the cpu to 0 and be done with it. I'll pick up Prarits patch and amend it. Thanks, tglx _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec