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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 CCBFFC46470 for ; Thu, 30 May 2019 04:14:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9BF98251EB for ; Thu, 30 May 2019 04:14:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559189656; bh=nI/XTBVuAqM8axkiFf/VzEf3Bc+uambo+F/BfG6LJJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lba8nzuCtB4UhylQOrLylbu2eAKgJ0d95a21NRVyeKH95C1ToMMAJ+Rx0cVUjxi1+ AutQe9b/zqBsfFQxgG+9JQugduRwYbqHBJykaPnPLDBs/DnP7gjw5ixU71p4O5Avsp UNOIHw7nDuVcaJATyROXncagsHChFZWs10ZUXaq8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726935AbfE3EOK (ORCPT ); Thu, 30 May 2019 00:14:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:41614 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730628AbfE3DQO (ORCPT ); Wed, 29 May 2019 23:16:14 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 D1EE22458C; Thu, 30 May 2019 03:16:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559186173; bh=nI/XTBVuAqM8axkiFf/VzEf3Bc+uambo+F/BfG6LJJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DX6gHY10iCkuSwf0n2bw1Rf2XE48MVQOehV+NSaEgAJGS4Ns+bHYcr7pq7oW9v9Na GC2WMOq1fuN59VdQeYI0YoRBmmzTsLGzLLrWwc7x+lmoxUCSj9jpSJTMjLjg8uSTAm wIwUaCnmCufAbLciI+zdnun59RQ71zf7PhHieutw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Paul E. McKenney" , Peter Zijlstra , Andrea Parri , Ming Lei , Jens Axboe , Omar Sandoval , linux-block@vger.kernel.org Subject: [PATCH 4.19 007/276] sbitmap: fix improper use of smp_mb__before_atomic() Date: Wed, 29 May 2019 20:02:45 -0700 Message-Id: <20190530030523.903699362@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030523.133519668@linuxfoundation.org> References: <20190530030523.133519668@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Andrea Parri commit a0934fd2b1208458e55fc4b48f55889809fce666 upstream. This barrier only applies to the read-modify-write operations; in particular, it does not apply to the atomic_set() primitive. Replace the barrier with an smp_mb(). Fixes: 6c0ca7ae292ad ("sbitmap: fix wakeup hang after sbq resize") Cc: stable@vger.kernel.org Reported-by: "Paul E. McKenney" Reported-by: Peter Zijlstra Signed-off-by: Andrea Parri Reviewed-by: Ming Lei Cc: Jens Axboe Cc: Omar Sandoval Cc: Ming Lei Cc: linux-block@vger.kernel.org Cc: "Paul E. McKenney" Cc: Peter Zijlstra Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- lib/sbitmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -356,7 +356,7 @@ static void sbitmap_queue_update_wake_ba * to ensure that the batch size is updated before the wait * counts. */ - smp_mb__before_atomic(); + smp_mb(); for (i = 0; i < SBQ_WAIT_QUEUES; i++) atomic_set(&sbq->ws[i].wait_cnt, 1); }