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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 4441AC433FF for ; Mon, 12 Aug 2019 12:25:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 241D921744 for ; Mon, 12 Aug 2019 12:25:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728799AbfHLMZN (ORCPT ); Mon, 12 Aug 2019 08:25:13 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:4660 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728464AbfHLMZM (ORCPT ); Mon, 12 Aug 2019 08:25:12 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 3FD46459B3490B51E00F; Mon, 12 Aug 2019 20:25:10 +0800 (CST) Received: from RH5885H-V3.huawei.com (10.90.53.225) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.439.0; Mon, 12 Aug 2019 20:25:03 +0800 From: Sun Ke To: , , , , , Subject: [PATCH] nbd: add a missed nbd_config_put() in nbd_xmit_timeout() Date: Mon, 12 Aug 2019 20:31:26 +0800 Message-ID: <1565613086-13776-1-git-send-email-sunke32@huawei.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.90.53.225] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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), -- 2.7.4