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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 EC139C433FF for ; Thu, 15 Aug 2019 01:27:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CAB392084F for ; Thu, 15 Aug 2019 01:27:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728972AbfHOB1U (ORCPT ); Wed, 14 Aug 2019 21:27:20 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:57076 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727822AbfHOB1U (ORCPT ); Wed, 14 Aug 2019 21:27:20 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 8239D636284E109C16C6; Thu, 15 Aug 2019 09:27:18 +0800 (CST) Received: from [127.0.0.1] (10.184.194.169) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.439.0; Thu, 15 Aug 2019 09:27:14 +0800 Subject: Re: [PATCH] nbd: add a missed nbd_config_put() in nbd_xmit_timeout() To: , , , , References: <1565613086-13776-1-git-send-email-sunke32@huawei.com> From: "sunke (E)" Message-ID: <05b3cd4a-d2c1-5ad7-7a39-64bac470032a@huawei.com> Date: Thu, 15 Aug 2019 09:27:13 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <1565613086-13776-1-git-send-email-sunke32@huawei.com> Content-Type: text/plain; charset="gbk"; format=flowed Content-Transfer-Encoding: 8bit X-Originating-IP: [10.184.194.169] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ping ÔÚ 2019/8/12 20:31, Sun Ke дµÀ: > When try to get the lock failed, before return, execute the > nbd_config_put() to decrease the nbd->config_refs. > > If the nbd->config_refs is added but not decreased. Then will not > execute nbd_clear_sock() in nbd_config_put(). bd->task_setup will > not be cleared away. Finally, print"Device being setup by another > task" in nbd_add_sock() and nbd device can not be reused. > > Fixes: 8f3ea35929a0 ("nbd: handle unexpected replies better") > Signed-off-by: Sun Ke > --- > drivers/block/nbd.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c > index e21d2de..a69a90a 100644 > --- a/drivers/block/nbd.c > +++ b/drivers/block/nbd.c > @@ -357,8 +357,10 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req, > } > config = nbd->config; > > - if (!mutex_trylock(&cmd->lock)) > + if (!mutex_trylock(&cmd->lock)) { > + nbd_config_put(nbd); > return BLK_EH_RESET_TIMER; > + } > > if (config->num_connections > 1) { > dev_err_ratelimited(nbd_to_dev(nbd), >