From patchwork Sat Jul 2 05:00:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tetsuo Handa X-Patchwork-Id: 586731 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E2669C43334 for ; Sat, 2 Jul 2022 05:00:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231293AbiGBFAc (ORCPT ); Sat, 2 Jul 2022 01:00:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229486AbiGBFAb (ORCPT ); Sat, 2 Jul 2022 01:00:31 -0400 Received: from www262.sakura.ne.jp (www262.sakura.ne.jp [202.181.97.72]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 689041ADA4 for ; Fri, 1 Jul 2022 22:00:30 -0700 (PDT) Received: from fsav412.sakura.ne.jp (fsav412.sakura.ne.jp [133.242.250.111]) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTP id 26250KZs060271; Sat, 2 Jul 2022 14:00:20 +0900 (JST) (envelope-from penguin-kernel@I-love.SAKURA.ne.jp) Received: from www262.sakura.ne.jp (202.181.97.72) by fsav412.sakura.ne.jp (F-Secure/fsigk_smtp/550/fsav412.sakura.ne.jp); Sat, 02 Jul 2022 14:00:20 +0900 (JST) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/fsav412.sakura.ne.jp) Received: from [192.168.1.9] (M106072142033.v4.enabler.ne.jp [106.72.142.33]) (authenticated bits=0) by www262.sakura.ne.jp (8.15.2/8.15.2) with ESMTPSA id 26250KMU060264 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NO); Sat, 2 Jul 2022 14:00:20 +0900 (JST) (envelope-from penguin-kernel@I-love.SAKURA.ne.jp) Message-ID: <9e454c72-5af2-5de3-db86-d27f699fa0c0@I-love.SAKURA.ne.jp> Date: Sat, 2 Jul 2022 14:00:20 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: [PATCH v3 3/4] scsi: qla2xxx: always wait for qlt_sess_work_fn() from qlt_stop_phase1() Content-Language: en-US From: Tetsuo Handa To: Nilesh Javali , GR-QLogic-Storage-Upstream@marvell.com, "James E.J. Bottomley" , "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org References: <46629616-be04-9a53-b9d8-b2b947adf9d0@I-love.SAKURA.ne.jp> In-Reply-To: <46629616-be04-9a53-b9d8-b2b947adf9d0@I-love.SAKURA.ne.jp> Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Currently qlt_stop_phase1() may fail to call flush_scheduled_work(), for list_empty() may return true as soon as qlt_sess_work_fn() called list_del(). In order to close this race window, check list_empty() after calling flush_scheduled_work(). If this patch causes problems, please check commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue() using a macro"). We are on the way to remove all flush_scheduled_work() calls from the kernel. Signed-off-by: Tetsuo Handa --- This patch is only compile tested. drivers/scsi/qla2xxx/qla_target.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c index b170ebbd05b7..9013c162d4aa 100644 --- a/drivers/scsi/qla2xxx/qla_target.c +++ b/drivers/scsi/qla2xxx/qla_target.c @@ -1557,11 +1557,11 @@ int qlt_stop_phase1(struct qla_tgt *tgt) ql_dbg(ql_dbg_tgt_mgt, vha, 0xf009, "Waiting for sess works (tgt %p)", tgt); spin_lock_irqsave(&tgt->sess_work_lock, flags); - while (!list_empty(&tgt->sess_works_list)) { + do { spin_unlock_irqrestore(&tgt->sess_work_lock, flags); flush_scheduled_work(); spin_lock_irqsave(&tgt->sess_work_lock, flags); - } + } while (!list_empty(&tgt->sess_works_list)); spin_unlock_irqrestore(&tgt->sess_work_lock, flags); ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00a,