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=-14.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE, 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 98828C388F9 for ; Wed, 11 Nov 2020 08:25:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D0EA206E3 for ; Wed, 11 Nov 2020 08:25:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="GaKczrZ8"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="q8fTu8ad" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726723AbgKKIZT (ORCPT ); Wed, 11 Nov 2020 03:25:19 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:36242 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725900AbgKKIXS (ORCPT ); Wed, 11 Nov 2020 03:23:18 -0500 Date: Wed, 11 Nov 2020 08:23:15 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1605082996; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CmUOAzd/LeEYd+KOnMpvs/VAGk9M9APMi0iAuTcP/Eg=; b=GaKczrZ8wG3VF7+wZjIUc5Nv4xy3zQl+OiOWWI2DbooY61wkYP/hJtf4qh/XTgRVBppllH f9ej0GZdKxm/ZpkAQmM93aoRQGRUB73jgoMCtFBlwM0uPqs4y5My1QcbT7Pz9p+C3JJMCa RON6Dt3YRLiwWFZS5yk7539VvpA5sp0fKlKnqCd4LONR+6N3dYjC6qp78aoghcqg0yCDA3 T2hjbBjy2Mjlg2mCGflOXCHaD3ugXXghB3a02hbCU/JB5CvUzXhnfLS/v/krEA1DbAmXxY 2NZ9bAQ1YMBtWuM8xbzJoRfIdGxFgmXC5CFaozDHBEGZYAA9QOn9JvF4RatD4A== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1605082996; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CmUOAzd/LeEYd+KOnMpvs/VAGk9M9APMi0iAuTcP/Eg=; b=q8fTu8ad/Zuew/yYmSJXuYrvHo5115ci2oDroMlj27UV2Icujj5/p6vQmSVuvT6v1seuqK FZM/FCF01MzCJHCQ== From: "tip-bot2 for Valentin Schneider" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched: Deny self-issued __set_cpus_allowed_ptr() when migrate_disable() Cc: Valentin Schneider , "Peter Zijlstra (Intel)" , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20201013140116.26651-1-valentin.schneider@arm.com> References: <20201013140116.26651-1-valentin.schneider@arm.com> MIME-Version: 1.0 Message-ID: <160508299532.11244.16920106537072261900.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the sched/core branch of tip: Commit-ID: 885b3ba47aa5cc16550beb8a42181ad5e8302ceb Gitweb: https://git.kernel.org/tip/885b3ba47aa5cc16550beb8a42181ad5e8302ceb Author: Valentin Schneider AuthorDate: Tue, 13 Oct 2020 15:01:15 +01:00 Committer: Peter Zijlstra CommitterDate: Tue, 10 Nov 2020 18:39:02 +01:00 sched: Deny self-issued __set_cpus_allowed_ptr() when migrate_disable() migrate_disable(); set_cpus_allowed_ptr(current, {something excluding task_cpu(current)}); affine_move_task(); <-- never returns Signed-off-by: Valentin Schneider Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20201013140116.26651-1-valentin.schneider@arm.com --- kernel/sched/core.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index e92d785..88c6fcb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2238,8 +2238,17 @@ static int __set_cpus_allowed_ptr(struct task_struct *p, goto out; } - if (!(flags & SCA_MIGRATE_ENABLE) && cpumask_equal(&p->cpus_mask, new_mask)) - goto out; + if (!(flags & SCA_MIGRATE_ENABLE)) { + if (cpumask_equal(&p->cpus_mask, new_mask)) + goto out; + + if (WARN_ON_ONCE(p == current && + is_migration_disabled(p) && + !cpumask_test_cpu(task_cpu(p), new_mask))) { + ret = -EBUSY; + goto out; + } + } /* * Picking a ~random cpu helps in cases where we are changing affinity