From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 35B9AC432C1 for ; Tue, 24 Sep 2019 09:18:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0372A214AF for ; Tue, 24 Sep 2019 09:18:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="EU4LTSeT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2395148AbfIXJSS (ORCPT ); Tue, 24 Sep 2019 05:18:18 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:43950 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727531AbfIXJSR (ORCPT ); Tue, 24 Sep 2019 05:18:17 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=YSjhyC1lKRB8fubVQEKHM7jmo9vsi65UYntnwYqseFQ=; b=EU4LTSeTtqxV9VDJrpZZt3ruH RnUeZYjlATkQ+o+C5+ROiZN27BBCfJWvlJpGuODkYxVTtV62XtX5u+/TfEtKgPtYuC1803wzuLpmo 2NRs9TVIz3ep1Zn+JQmSdFozMjFEhHRxbvq6pJ8YgKJQi1fnRNB5AVgendjVY4EWEXJowjIdPUNCR WZaGzFSLI4kXTXE7qfdf1cSuSQDZmjTppV6oJ3/si42aaiLKltB1HLzzHaiUrFMFRHaV79PqFrXdK IIp4fjZa25loT69yYYRij/2g28K/hwTv9jO6JUBcBR5pKvlor6U9wf3iG2lizQwQog4BTjN5YHPBa CXn6Y9B3w==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.2 #3 (Red Hat Linux)) id 1iCgwi-0007gZ-I9; Tue, 24 Sep 2019 09:17:20 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 61313305E35; Tue, 24 Sep 2019 11:16:29 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id E73F720D80D41; Tue, 24 Sep 2019 11:17:14 +0200 (CEST) Date: Tue, 24 Sep 2019 11:17:14 +0200 From: Peter Zijlstra To: Michal Hocko Cc: Yunsheng Lin , catalin.marinas@arm.com, will@kernel.org, mingo@redhat.com, bp@alien8.de, rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, heiko.carstens@de.ibm.com, gor@linux.ibm.com, borntraeger@de.ibm.com, ysato@users.sourceforge.jp, dalias@libc.org, davem@davemloft.net, ralf@linux-mips.org, paul.burton@mips.com, jhogan@kernel.org, jiaxun.yang@flygoat.com, chenhc@lemote.com, akpm@linux-foundation.org, rppt@linux.ibm.com, anshuman.khandual@arm.com, tglx@linutronix.de, cai@lca.pw, robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com, x86@kernel.org, dave.hansen@linux.intel.com, luto@kernel.org, len.brown@intel.com, axboe@kernel.dk, dledford@redhat.com, jeffrey.t.kirsher@intel.com, linux-alpha@vger.kernel.org, naveen.n.rao@linux.vnet.ibm.com, mwb@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, tbogendoerfer@suse.de, linux-mips@vger.kernel.org, rafael@kernel.org, gregkh@linuxfoundation.org Subject: Re: [PATCH v6] numa: make node_to_cpumask_map() NUMA_NO_NODE aware Message-ID: <20190924091714.GJ2369@hirez.programming.kicks-ass.net> References: <1568724534-146242-1-git-send-email-linyunsheng@huawei.com> <20190923151519.GE2369@hirez.programming.kicks-ass.net> <20190923152856.GB17206@dhcp22.suse.cz> <20190923154852.GG2369@hirez.programming.kicks-ass.net> <20190923165235.GD17206@dhcp22.suse.cz> <20190923203410.GI2369@hirez.programming.kicks-ass.net> <20190924074751.GB23050@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190924074751.GB23050@dhcp22.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 24, 2019 at 09:47:51AM +0200, Michal Hocko wrote: > On Mon 23-09-19 22:34:10, Peter Zijlstra wrote: > > On Mon, Sep 23, 2019 at 06:52:35PM +0200, Michal Hocko wrote: > [...] > > > I even the > > > ACPI standard is considering this optional. Yunsheng Lin has referred to > > > the specific part of the standard in one of the earlier discussions. > > > Trying to guess the node affinity is worse than providing all CPUs IMHO. > > > > I'm saying the ACPI standard is wrong. > > Even if you were right on this the reality is that a HW is likely to > follow that standard and we cannot rule out NUMA_NO_NODE being > specified. As of now we would access beyond the defined array and that > is clearly a bug. Right, because the device node is wrong, so we fix _that_! > Let's assume that this is really a bug for a moment. What are you going > to do about that? BUG_ON? I do not really see any solution besides to either > provide something sensible or BUG_ON. If you are worried about a > conditional then this should be pretty easy to solve by starting the > array at -1 index and associate it with the online cpu mask. The same thing I proposed earlier; force the device node to 0 (or any other convenient random valid value) and issue a FW_BUG message to the console.