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, USER_AGENT_SANE_1 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 F0F02C3A5A0 for ; Mon, 20 Apr 2020 06:55:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D031F221F4 for ; Mon, 20 Apr 2020 06:55:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726089AbgDTGzw (ORCPT ); Mon, 20 Apr 2020 02:55:52 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:45398 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725815AbgDTGzv (ORCPT ); Mon, 20 Apr 2020 02:55:51 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id BCF396C3F37183F6F41D; Mon, 20 Apr 2020 14:55:49 +0800 (CST) Received: from [127.0.0.1] (10.166.215.235) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Mon, 20 Apr 2020 14:55:39 +0800 Subject: Re: bcache: unlock new_nodes[i]->write_lock in btree_gc_coalesce From: Zhiqiang Liu To: , , , CC: "wubo (T)" , Mingfangsen , Yanxiaodan , linfeilong References: Message-ID: Date: Mon, 20 Apr 2020 14:55:38 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [10.166.215.235] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org friendly ping... On 2020/4/15 19:42, Zhiqiang Liu wrote: > From: Zhiqiang Liu > > coccicheck reports: > drivers/md//bcache/btree.c:1538:1-7: preceding lock on line 1417 > > After obtaining new_nodes[i]->write_lock, we may go to out_nocoalesce > tag without releasing lock. Here, we add a new tag > 'out_unlock_nocoalesce' before out_nocoalesce tag to release > new_nodes[i]->write_lock. > > Fixes: 2a285686c1 ("bcache: btree locking rework") > Signed-off-by: Zhiqiang Liu > --- > drivers/md/bcache/btree.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c > index fa872df4e770..cad8b0b97e33 100644 > --- a/drivers/md/bcache/btree.c > +++ b/drivers/md/bcache/btree.c > @@ -1447,7 +1447,7 @@ static int btree_gc_coalesce(struct btree *b, struct btree_op *op, > if (__set_blocks(n1, n1->keys + n2->keys, > block_bytes(b->c)) > > btree_blocks(new_nodes[i])) > - goto out_nocoalesce; > + goto out_unlock_nocoalesce; > > keys = n2->keys; > /* Take the key of the node we're getting rid of */ > @@ -1476,7 +1476,7 @@ static int btree_gc_coalesce(struct btree *b, struct btree_op *op, > > if (__bch_keylist_realloc(&keylist, > bkey_u64s(&new_nodes[i]->key))) > - goto out_nocoalesce; > + goto out_unlock_nocoalesce; > > bch_btree_node_write(new_nodes[i], &cl); > bch_keylist_add(&keylist, &new_nodes[i]->key); > @@ -1522,6 +1522,10 @@ static int btree_gc_coalesce(struct btree *b, struct btree_op *op, > /* Invalidated our iterator */ > return -EINTR; > > +out_unlock_nocoalesce: > + for (i = 0; i < nodes; i++) > + mutex_unlock(&new_nodes[i]->write_lock); > + > out_nocoalesce: > closure_sync(&cl); >