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=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 9CB5DC352AA for ; Tue, 1 Oct 2019 07:19:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6AD6E2133F for ; Tue, 1 Oct 2019 07:19:30 +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="m3A8xuj7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732917AbfJAHT3 (ORCPT ); Tue, 1 Oct 2019 03:19:29 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:46138 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732725AbfJAHT3 (ORCPT ); Tue, 1 Oct 2019 03:19:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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=0S4ysf7rtEXMw/wzlhBR7mecKndwZrv5Pmb3IJaLSgg=; b=m3A8xuj7lSd8uA0UiO7usiyK1 lWfWPn18pSufTimJhZhxZ3t462/KQ5tkb4LDSl856RYyURl7AvhZR0gL5ZVxumlT92Mo1NA22oL8x 8ZclaWrkh1IR7TyYByKTKoiPDSxSRFuRlKu4t2kjhGauy2eisdedXYFN806TYANNDDPsI0otheNN7 rbqHu9jbbH/lj36Gf5f6rCWXWBHxa2JE5W+jO4JzN8foT2rPe5XmCwveyzkjc9SBhP3pUIrXCvbJ7 PczCnK+Dg4P060tJ+lnBFIbYTS/K6ksh4nW2PNT+yEBl0tPozZT79AVxMCNSVAyIWZzqGedb8O/zk 6n2lK7MRg==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by bombadil.infradead.org with esmtpsa (Exim 4.92.2 #3 (Red Hat Linux)) id 1iFCRQ-0001vn-Ff; Tue, 01 Oct 2019 07:19:24 +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 3CD4430477A; Tue, 1 Oct 2019 09:18:33 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 7D9B8265261AA; Tue, 1 Oct 2019 09:19:21 +0200 (CEST) Date: Tue, 1 Oct 2019 09:19:21 +0200 From: Peter Zijlstra To: John Stultz Cc: Ingo Molnar , Linus Torvalds , Linux Kernel Mailing List , Thomas Gleixner , Andrew Morton , Mathieu Desnoyers , "Eric W. Biederman" , Joel Fernandes , Alistair Delva Subject: Re: [GIT PULL] scheduler fixes Message-ID: <20191001071921.GJ4519@hirez.programming.kicks-ass.net> References: <20190928123905.GA97048@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Sep 30, 2019 at 04:45:49PM -0700, John Stultz wrote: > Reverting the following patches: > "sched/membarrier: Fix p->mm->membarrier_state racy load" ARGH, I fudged it... please try: diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index a39bed2c784f..168479a7d61b 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -174,7 +174,6 @@ static int membarrier_private_expedited(int flags) */ if (cpu == raw_smp_processor_id()) continue; - rcu_read_lock(); p = rcu_dereference(cpu_rq(cpu)->curr); if (p && p->mm == mm) __cpumask_set_cpu(cpu, tmpmask);