From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:33260 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934160AbeGFFvS (ORCPT ); Fri, 6 Jul 2018 01:51:18 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, NeilBrown , Shaohua Li , Jack Wang Subject: [PATCH 4.14 35/61] md: dont call bitmap_create() while array is quiesced. Date: Fri, 6 Jul 2018 07:46:59 +0200 Message-Id: <20180706054713.679536995@linuxfoundation.org> In-Reply-To: <20180706054712.332416244@linuxfoundation.org> References: <20180706054712.332416244@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: NeilBrown commit 52a0d49de3d592a3118e13f35985e3d99eaf43df upstream. bitmap_create() allocates memory with GFP_KERNEL and so can wait for IO. If called while the array is quiesced, it could wait indefinitely for write out to the array - deadlock. So call bitmap_create() before quiescing the array. Signed-off-by: NeilBrown Signed-off-by: Shaohua Li Signed-off-by: Jack Wang Signed-off-by: Greg Kroah-Hartman --- drivers/md/md.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6645,22 +6645,26 @@ static int set_bitmap_file(struct mddev return -ENOENT; /* cannot remove what isn't there */ err = 0; if (mddev->pers) { - mddev->pers->quiesce(mddev, 1); if (fd >= 0) { struct bitmap *bitmap; bitmap = bitmap_create(mddev, -1); + mddev->pers->quiesce(mddev, 1); if (!IS_ERR(bitmap)) { mddev->bitmap = bitmap; err = bitmap_load(mddev); } else err = PTR_ERR(bitmap); - } - if (fd < 0 || err) { + if (err) { + bitmap_destroy(mddev); + fd = -1; + } + mddev->pers->quiesce(mddev, 0); + } else if (fd < 0) { + mddev->pers->quiesce(mddev, 1); bitmap_destroy(mddev); - fd = -1; /* make sure to put the file */ + mddev->pers->quiesce(mddev, 0); } - mddev->pers->quiesce(mddev, 0); } if (fd < 0) { struct file *f = mddev->bitmap_info.file; @@ -6944,8 +6948,8 @@ static int update_array_info(struct mdde mddev->bitmap_info.default_offset; mddev->bitmap_info.space = mddev->bitmap_info.default_space; - mddev->pers->quiesce(mddev, 1); bitmap = bitmap_create(mddev, -1); + mddev->pers->quiesce(mddev, 1); if (!IS_ERR(bitmap)) { mddev->bitmap = bitmap; rv = bitmap_load(mddev);