From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:35334 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728556AbeIMTN1 (ORCPT ); Thu, 13 Sep 2018 15:13:27 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anand Jain , David Sterba , Sasha Levin Subject: [PATCH 4.18 149/197] btrfs: lift uuid_mutex to callers of btrfs_parse_early_options Date: Thu, 13 Sep 2018 15:31:38 +0200 Message-Id: <20180913131847.511999376@linuxfoundation.org> In-Reply-To: <20180913131841.568116777@linuxfoundation.org> References: <20180913131841.568116777@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: David Sterba [ Upstream commit 5139cff598d42b1e531f40c84691a7e945f04553 ] Prepartory work to fix race between mount and device scan. btrfs_parse_early_options calls the device scan from mount and we'll need to let mount completely manage the critical section. Reviewed-by: Anand Jain Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/super.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -892,6 +892,8 @@ static int btrfs_parse_early_options(con char *device_name, *opts, *orig, *p; int error = 0; + lockdep_assert_held(&uuid_mutex); + if (!options) return 0; @@ -917,10 +919,8 @@ static int btrfs_parse_early_options(con error = -ENOMEM; goto out; } - mutex_lock(&uuid_mutex); error = btrfs_scan_one_device(device_name, flags, holder, fs_devices); - mutex_unlock(&uuid_mutex); kfree(device_name); if (error) goto out; @@ -1528,8 +1528,10 @@ static struct dentry *btrfs_mount_root(s if (!(flags & SB_RDONLY)) mode |= FMODE_WRITE; + mutex_lock(&uuid_mutex); error = btrfs_parse_early_options(data, mode, fs_type, &fs_devices); + mutex_unlock(&uuid_mutex); if (error) { return ERR_PTR(error); }