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=-11.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 E2482C63798 for ; Wed, 21 Jul 2021 12:01:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 710B361375 for ; Wed, 21 Jul 2021 12:01:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237498AbhGULT7 (ORCPT ); Wed, 21 Jul 2021 07:19:59 -0400 Received: from foss.arm.com ([217.140.110.172]:52750 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237424AbhGULKw (ORCPT ); Wed, 21 Jul 2021 07:10:52 -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 38A336D; Wed, 21 Jul 2021 04:51:29 -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 BB4C63F694; Wed, 21 Jul 2021 04:51:26 -0700 (PDT) From: Valentin Schneider To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rt-users@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Ingo Molnar , Peter Zijlstra , Thomas Gleixner , Steven Rostedt , Daniel Bristot de Oliveira , "Paul E. McKenney" , Josh Triplett , Mathieu Desnoyers , Lai Jiangshan , Joel Fernandes , Anshuman Khandual , Vincenzo Frascino , Steven Price , Ard Biesheuvel Subject: [PATCH 0/3] sched: migrate_disable() vs per-CPU access safety checks Date: Wed, 21 Jul 2021 12:51:15 +0100 Message-Id: <20210721115118.729943-1-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 Hi folks, I've hit a few warnings when taking v5.13-rt1 out for a spin on my arm64 Juno. Those are due to regions that become preemptible under PREEMPT_RT, but remain safe wrt per-CPU accesses due to migrate_disable() + a sleepable lock. This adds a helper that looks at not just preemptability but also affinity and migrate disable, and plasters the warning sites. Cheers, Valentin Valentin Schneider (3): sched: Introduce is_pcpu_safe() rcu/nocb: Check for migratability rather than pure preemptability arm64: mm: Make arch_faults_on_old_pte() check for migratability arch/arm64/include/asm/pgtable.h | 2 +- include/linux/sched.h | 10 ++++++++++ kernel/rcu/tree_plugin.h | 3 +-- 3 files changed, 12 insertions(+), 3 deletions(-) -- 2.25.1