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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 63CB4C433C1 for ; Wed, 24 Mar 2021 18:55:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D6EA619EC for ; Wed, 24 Mar 2021 18:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237726AbhCXSyh (ORCPT ); Wed, 24 Mar 2021 14:54:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:55680 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237571AbhCXSyd (ORCPT ); Wed, 24 Mar 2021 14:54:33 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id BC4E961A07; Wed, 24 Mar 2021 18:54:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1616612073; bh=8fWPNDYKXJqAFEWuKiNC/u4xN9UBeB93KGJ+cFLB/58=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Y5s/EiFwG7iGYKvQ+qcNVg6I4vBZhsw8bSKBZKr2omh0QBqMEou7s1ddnRXMp60i5 GP2srrVXjdUz8dahnI9GubC6fxM0UdWGjCbFNsqm2BQL79w6pZ84A+Qz0fdlxO9IvY m8UUoAz3PUKls12i+TbhnYcesfpJ13A5LnK5YjZg= Date: Wed, 24 Mar 2021 11:54:32 -0700 From: Andrew Morton To: Valentin Schneider Cc: linux-kernel@vger.kernel.org, "linux-ia64@vger.kernel.org" , debian-ia64 , John Paul Adrian Glaubitz , "Peter Zijlstra (Intel)" , Ingo Molnar , Vincent Guittot , Dietmar Eggemann , Sergei Trofimovich , Anatoly Pugachev Subject: Re: [PATCH] ia64: Ensure proper NUMA distance and possible map initialization Message-Id: <20210324115432.4102cd93d35a2edb1742dec7@linux-foundation.org> In-Reply-To: <20210318130617.896309-1-valentin.schneider@arm.com> References: <20210318130617.896309-1-valentin.schneider@arm.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 18 Mar 2021 13:06:17 +0000 Valentin Schneider wrote: > John Paul reported a warning about bogus NUMA distance values spurred by > commit: > > 620a6dc40754 ("sched/topology: Make sched_init_numa() use a set for the deduplicating sort") > > In this case, the afflicted machine comes up with a reported 256 possible > nodes, all of which are 0 distance away from one another. This was > previously silently ignored, but is now caught by the aforementioned > commit. > > The culprit is ia64's node_possible_map which remains unchanged from its > initialization value of NODE_MASK_ALL. In John's case, the machine doesn't > have any SRAT nor SLIT table, but AIUI the possible map remains untouched > regardless of what ACPI tables end up being parsed. Thus, !online && > possible nodes remain with a bogus distance of 0 (distances \in [0, 9] are > "reserved and have no meaning" as per the ACPI spec). > > Follow x86 / drivers/base/arch_numa's example and set the possible map to > the parsed map, which in this case seems to be the online map. > > Link: http://lore.kernel.org/r/255d6b5d-194e-eb0e-ecdd-97477a534441@physik.fu-berlin.de > Fixes: 620a6dc40754 ("sched/topology: Make sched_init_numa() use a set for the deduplicating sort") > Reported-by: John Paul Adrian Glaubitz > Signed-off-by: Valentin Schneider > --- > This might need an earlier Fixes: tag, but all of this is quite old and > dusty (the git blame rabbit hole leads me to ~2008/2007) > Thanks. Is this worth a cc:stable tag?