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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 EC70FC433E1 for ; Tue, 26 May 2020 18:55:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9B8E20849 for ; Tue, 26 May 2020 18:55:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519331; bh=FqIUcj0/zvBYNmeMXGFKy3xHDAfAvI/YMYfqC8HiR6s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=l0hs/IHrNF4Hu/avvxYxQV0fQ5nSEfdJkQUnpj9ZmH+ECA0ImNLjF13o6lsQsC0V3 DaIVfIkv7UwvY5hLQ9XZHiv39G/kjAD1Vp+sTL/C37wjyxsTusKyMoLwdoPR6lnRwD xxDhATq3cASO6lHW+xjnCDpUrg3dgpct2l6t2zZs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389533AbgEZSzb (ORCPT ); Tue, 26 May 2020 14:55:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:47876 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389505AbgEZSz2 (ORCPT ); Tue, 26 May 2020 14:55:28 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 724A820849; Tue, 26 May 2020 18:55:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519327; bh=FqIUcj0/zvBYNmeMXGFKy3xHDAfAvI/YMYfqC8HiR6s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oVFLyRh6YGGyTju0o37v0LIgChb0+aBf91sqWfncVNgEEI9gnpz2I6E1HawAgGzNH STbXWW2bGcc2hmijlQffXFxsglaaLmlf3Y3uZr9+CF4pruQXYnD6Ydn34eabhRlAtC VOxunMiCRPPztw793szzQaH8gFEs7WUEIu2rMDnU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mathias Krause , Herbert Xu , Daniel Jordan , Sasha Levin Subject: [PATCH 4.4 25/65] padata: set cpu_index of unused CPUs to -1 Date: Tue, 26 May 2020 20:52:44 +0200 Message-Id: <20200526183915.603271344@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183905.988782958@linuxfoundation.org> References: <20200526183905.988782958@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mathias Krause [ Upstream commit 1bd845bcb41d5b7f83745e0cb99273eb376f2ec5 ] The parallel queue per-cpu data structure gets initialized only for CPUs in the 'pcpu' CPU mask set. This is not sufficient as the reorder timer may run on a different CPU and might wrongly decide it's the target CPU for the next reorder item as per-cpu memory gets memset(0) and we might be waiting for the first CPU in cpumask.pcpu, i.e. cpu_index 0. Make the '__this_cpu_read(pd->pqueue->cpu_index) == next_queue->cpu_index' compare in padata_get_next() fail in this case by initializing the cpu_index member of all per-cpu parallel queues. Use -1 for unused ones. Signed-off-by: Mathias Krause Signed-off-by: Herbert Xu Signed-off-by: Daniel Jordan Signed-off-by: Sasha Levin --- kernel/padata.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/padata.c b/kernel/padata.c index 8aef48c3267b..4f860043a8e5 100644 --- a/kernel/padata.c +++ b/kernel/padata.c @@ -461,8 +461,14 @@ static void padata_init_pqueues(struct parallel_data *pd) struct padata_parallel_queue *pqueue; cpu_index = 0; - for_each_cpu(cpu, pd->cpumask.pcpu) { + for_each_possible_cpu(cpu) { pqueue = per_cpu_ptr(pd->pqueue, cpu); + + if (!cpumask_test_cpu(cpu, pd->cpumask.pcpu)) { + pqueue->cpu_index = -1; + continue; + } + pqueue->pd = pd; pqueue->cpu_index = cpu_index; cpu_index++; -- 2.25.1