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=-5.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 B64F7C47E49 for ; Wed, 30 Oct 2019 10:16:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B6492087E for ; Wed, 30 Oct 2019 10:16:35 +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="R7ox8vy3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726413AbfJ3KQb (ORCPT ); Wed, 30 Oct 2019 06:16:31 -0400 Received: from merlin.infradead.org ([205.233.59.134]:49804 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726071AbfJ3KQb (ORCPT ); Wed, 30 Oct 2019 06:16:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.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=1zcHzV6zD9O31in8kloh0B+z/m7z7NmzyB+w3XnQ5n0=; b=R7ox8vy3ZnrhdMdpFSPLH1wLK vjbto6CkcTHdr4TJVIm3ERYb4ndeFEeQFraxfzpfbDzos7ani8v/0uI6sWTJELWdkjkKUalPdsQTS tl22rW36Q/iROk+G23RItInYa+B+jvCzzSVzNfAC0wiLxfcUuKVXCXZdr3FIIXlZ4Dfyn1uQ24eFC tl9g8DX8oZgSYA/CFZEIb+KktE50EeCeJONwTWEYqijdFf1mF+EN+3YEMjzL688bnj5c8oJDrn7AL PYm6mywIXQC9HQN6Xo3gs0E/F0l18VtctAko4q2TDwWxQR7TP7OZ6PppUcsHNZII8/TcsME8CL183 RgJzDI4Sg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iPl0D-0007W8-HX; Wed, 30 Oct 2019 10:14:57 +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 C03D4300596; Wed, 30 Oct 2019 11:13:48 +0100 (CET) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id DCD862B4574F7; Wed, 30 Oct 2019 11:14:49 +0100 (CET) Date: Wed, 30 Oct 2019 11:14:49 +0100 From: Peter Zijlstra To: Yunsheng Lin Cc: 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, mhocko@kernel.org, gregkh@linuxfoundation.org, bhelgaas@google.com, linux-pci@vger.kernel.org, rjw@rjwysocki.net, lenb@kernel.org, linux-acpi@vger.kernel.org Subject: Re: [PATCH v7] numa: make node_to_cpumask_map() NUMA_NO_NODE aware Message-ID: <20191030101449.GW4097@hirez.programming.kicks-ass.net> References: <1572428068-180880-1-git-send-email-linyunsheng@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1572428068-180880-1-git-send-email-linyunsheng@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Wed, Oct 30, 2019 at 05:34:28PM +0800, Yunsheng Lin wrote: > When passing the return value of dev_to_node() to cpumask_of_node() > without checking if the device's node id is NUMA_NO_NODE, there is > global-out-of-bounds detected by KASAN. > > From the discussion [1], NUMA_NO_NODE really means no node affinity, > which also means all cpus should be usable. So the cpumask_of_node() > should always return all cpus online when user passes the node id as > NUMA_NO_NODE, just like similar semantic that page allocator handles > NUMA_NO_NODE. > > But we cannot really copy the page allocator logic. Simply because the > page allocator doesn't enforce the near node affinity. It just picks it > up as a preferred node but then it is free to fallback to any other numa > node. This is not the case here and node_to_cpumask_map will only restrict > to the particular node's cpus which would have really non deterministic > behavior depending on where the code is executed. So in fact we really > want to return cpu_online_mask for NUMA_NO_NODE. > > Also there is a debugging version of node_to_cpumask_map() for x86 and > arm64, which is only used when CONFIG_DEBUG_PER_CPU_MAPS is defined, this > patch changes it to handle NUMA_NO_NODE as normal node_to_cpumask_map(). > > [1] https://lkml.org/lkml/2019/9/11/66 > Signed-off-by: Yunsheng Lin > Suggested-by: Michal Hocko > Acked-by: Michal Hocko > Acked-by: Paul Burton # MIPS bits Still: Nacked-by: Peter Zijlstra (Intel)