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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 08CB8C433E0 for ; Thu, 18 Mar 2021 13:08:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C7E9964F6E for ; Thu, 18 Mar 2021 13:08:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231304AbhCRNIR (ORCPT ); Thu, 18 Mar 2021 09:08:17 -0400 Received: from foss.arm.com ([217.140.110.172]:40610 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231244AbhCRNH6 (ORCPT ); Thu, 18 Mar 2021 09:07:58 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D1206ED1; Thu, 18 Mar 2021 06:07:57 -0700 (PDT) Received: from e113632-lin.cambridge.arm.com (e113632-lin.cambridge.arm.com [10.1.194.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5B9553F718; Thu, 18 Mar 2021 06:07:56 -0700 (PDT) From: Valentin Schneider To: linux-kernel@vger.kernel.org, "linux-ia64@vger.kernel.org" , debian-ia64 Cc: John Paul Adrian Glaubitz , "Peter Zijlstra (Intel)" , Ingo Molnar , Vincent Guittot , Dietmar Eggemann , Sergei Trofimovich , Anatoly Pugachev Subject: [PATCH] ia64: Ensure proper NUMA distance and possible map initialization Date: Thu, 18 Mar 2021 13:06:17 +0000 Message-Id: <20210318130617.896309-1-valentin.schneider@arm.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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) Alternatively, can we deprecate ia64 already? --- arch/ia64/kernel/acpi.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c index a5636524af76..e2af6b172200 100644 --- a/arch/ia64/kernel/acpi.c +++ b/arch/ia64/kernel/acpi.c @@ -446,7 +446,8 @@ void __init acpi_numa_fixup(void) if (srat_num_cpus == 0) { node_set_online(0); node_cpuid[0].phys_id = hard_smp_processor_id(); - return; + slit_distance(0, 0) = LOCAL_DISTANCE; + goto out; } /* @@ -489,7 +490,7 @@ void __init acpi_numa_fixup(void) for (j = 0; j < MAX_NUMNODES; j++) slit_distance(i, j) = i == j ? LOCAL_DISTANCE : REMOTE_DISTANCE; - return; + goto out; } memset(numa_slit, -1, sizeof(numa_slit)); @@ -514,6 +515,8 @@ void __init acpi_numa_fixup(void) printk("\n"); } #endif +out: + node_possible_map = node_online_map; } #endif /* CONFIG_ACPI_NUMA */ -- 2.25.1