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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 C6FE3CA9EAF for ; Sun, 27 Oct 2019 21:31:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9938A205C9 for ; Sun, 27 Oct 2019 21:31:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572211900; bh=sv62GLlzZY0YW5GNEa6kawtjMTNjMoGLeHqaa5Chwck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xDDWTwLY30W5Mdwj+sAsfPpoUCF/ZVNL76D0jnLtW58r6dLgMFlTC37c61tQhLvRw qaDMZMxmmF0Lrju29iVifJN+Dqz/EcygU2wRkIpJHtLFvNpq57pJDwf3QEOAsteLhN UPvNzF/zEIQKZUQDnxBOld8ohQ9qlDupOGkCI3P8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731529AbfJ0Vbj (ORCPT ); Sun, 27 Oct 2019 17:31:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:36346 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730878AbfJ0VQl (ORCPT ); Sun, 27 Oct 2019 17:16:41 -0400 Received: from localhost (100.50.158.77.rev.sfr.net [77.158.50.100]) (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 51B4421848; Sun, 27 Oct 2019 21:16:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572211000; bh=sv62GLlzZY0YW5GNEa6kawtjMTNjMoGLeHqaa5Chwck=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YOBlcMn8oloH0h/r6EOo7ZfDzNcaNmgZ+VAb7rhBK/PWUjM/Df6GjgiJhUNlrdEmp lpaWmngRBgVPr6IalfALrRUFSGsDvBoLR4Q6y2W1Y5gpKQ6Mx42jQkEz3khbsGfVYm ZDlpqKf5TRdi3NMRrmOKg8XXlE6xfdPnPwzeuHFY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tejun Heo , Josef Bacik , Jens Axboe Subject: [PATCH 4.19 92/93] blk-rq-qos: fix first node deletion of rq_qos_del() Date: Sun, 27 Oct 2019 22:01:44 +0100 Message-Id: <20191027203318.353148127@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191027203251.029297948@linuxfoundation.org> References: <20191027203251.029297948@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: Tejun Heo commit 307f4065b9d7c1e887e8bdfb2487e4638559fea1 upstream. rq_qos_del() incorrectly assigns the node being deleted to the head if it was the first on the list in the !prev path. Fix it by iterating with ** instead. Signed-off-by: Tejun Heo Cc: Josef Bacik Fixes: a79050434b45 ("blk-rq-qos: refactor out common elements of blk-wbt") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- block/blk-rq-qos.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) --- a/block/blk-rq-qos.h +++ b/block/blk-rq-qos.h @@ -80,16 +80,13 @@ static inline void rq_qos_add(struct req static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) { - struct rq_qos *cur, *prev = NULL; - for (cur = q->rq_qos; cur; cur = cur->next) { - if (cur == rqos) { - if (prev) - prev->next = rqos->next; - else - q->rq_qos = cur; + struct rq_qos **cur; + + for (cur = &q->rq_qos; *cur; cur = &(*cur)->next) { + if (*cur == rqos) { + *cur = rqos->next; break; } - prev = cur; } }