From patchwork Wed Nov 14 07:24:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lu Fengqi X-Patchwork-Id: 10681973 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 23E3B17F3 for ; Wed, 14 Nov 2018 07:25:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A74C2999C for ; Wed, 14 Nov 2018 07:25:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F338429CEF; Wed, 14 Nov 2018 07:25:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 718C629A2D for ; Wed, 14 Nov 2018 07:25:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731665AbeKNR1I (ORCPT ); Wed, 14 Nov 2018 12:27:08 -0500 Received: from mail.cn.fujitsu.com ([183.91.158.132]:58919 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727375AbeKNR1I (ORCPT ); Wed, 14 Nov 2018 12:27:08 -0500 X-IronPort-AV: E=Sophos;i="5.43,368,1503331200"; d="scan'208";a="48077927" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 14 Nov 2018 15:25:06 +0800 Received: from G08CNEXCHPEKD01.g08.fujitsu.local (unknown [10.167.33.80]) by cn.fujitsu.com (Postfix) with ESMTP id C8B034B714D6 for ; Wed, 14 Nov 2018 15:25:02 +0800 (CST) Received: from fnst.lan (10.167.226.155) by G08CNEXCHPEKD01.g08.fujitsu.local (10.167.33.89) with Microsoft SMTP Server (TLS) id 14.3.408.0; Wed, 14 Nov 2018 15:25:08 +0800 From: Lu Fengqi To: Subject: [PATCH] btrfs: Fix suspicious RCU usage warning in device_list_add Date: Wed, 14 Nov 2018 15:24:56 +0800 Message-ID: <20181114072456.4746-1-lufq.fnst@cn.fujitsu.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-Originating-IP: [10.167.226.155] X-yoursite-MailScanner-ID: C8B034B714D6.A6B54 X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: lufq.fnst@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Reviewed-by: Nikolay Borisov ============================= WARNING: suspicious RCU usage 4.20.0-rc2+ #23 Tainted: G O ----------------------------- fs/btrfs/volumes.c:886 suspicious rcu_dereference_check() usage! Use btrfs_info_in_rcu instead of pr_info for the required lock/unlock of RCU string. Fixes: 1f265fc6f58b ("btrfs: harden agaist duplicate fsid on scanned devices") Signed-off-by: Lu Fengqi --- fs/btrfs/volumes.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 2186300bab91..6039ae5c549e 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -873,15 +873,15 @@ static noinline struct btrfs_device *device_list_add(const char *path, if (device->bdev != path_bdev) { bdput(path_bdev); mutex_unlock(&fs_devices->device_list_mutex); - pr_warn( - "BTRFS: duplicate device fsid:devid for %pU:%llu old:%s new:%s\n", + btrfs_warn_in_rcu(device->fs_info, + "duplicate device fsid:devid for %pU:%llu old:%s new:%s\n", disk_super->fsid, devid, rcu_str_deref(device->name), path); return ERR_PTR(-EEXIST); } bdput(path_bdev); - pr_info( - "BTRFS: device fsid %pU devid %llu moved old:%s new:%s\n", + btrfs_info_in_rcu(device->fs_info, + "device fsid %pU devid %llu moved old:%s new:%s\n", disk_super->fsid, devid, rcu_str_deref(device->name), path); }