From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754204AbaK0IqE (ORCPT ); Thu, 27 Nov 2014 03:46:04 -0500 Received: from mail.kernel.org ([198.145.19.201]:41014 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754164AbaK0Ip7 (ORCPT ); Thu, 27 Nov 2014 03:45:59 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Al Viro , Zefan Li Subject: [PATCH 3.4 04/91] get rid of propagate_umount() mistakenly treating slaves as busy. Date: Thu, 27 Nov 2014 16:41:47 +0800 Message-Id: <1417077794-9299-4-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1417077368-9217-1-git-send-email-lizf@kernel.org> References: <1417077368-9217-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Al Viro 3.4.105-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 88b368f27a094277143d8ecd5a056116f6a41520 upstream. The check in __propagate_umount() ("has somebody explicitly mounted something on that slave?") is done *before* taking the already doomed victims out of the child lists. Signed-off-by: Al Viro [lizf: Backported to 3.4: - adjust context - s/hlist_for_each_entry/list_for_each_entry/] Signed-off-by: Zefan Li --- fs/namespace.c | 4 +++- fs/pnode.c | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/namespace.c b/fs/namespace.c index 4e46539..2985879 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1066,6 +1066,9 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill) for (p = mnt; p; p = next_mnt(p, mnt)) list_move(&p->mnt_hash, &tmp_list); + list_for_each_entry(p, &tmp_list, mnt_hash) + list_del_init(&p->mnt_child); + if (propagate) propagate_umount(&tmp_list); @@ -1076,7 +1079,6 @@ void umount_tree(struct mount *mnt, int propagate, struct list_head *kill) if (p->mnt_ns) __mnt_make_shortterm(p); p->mnt_ns = NULL; - list_del_init(&p->mnt_child); if (mnt_has_parent(p)) { p->mnt_parent->mnt_ghosts++; dentry_reset_mounted(p->mnt_mountpoint); diff --git a/fs/pnode.c b/fs/pnode.c index ab5fa9e..f61dcb4 100644 --- a/fs/pnode.c +++ b/fs/pnode.c @@ -333,8 +333,10 @@ static void __propagate_umount(struct mount *mnt) * umount the child only if the child has no * other children */ - if (child && list_empty(&child->mnt_mounts)) + if (child && list_empty(&child->mnt_mounts)) { + list_del_init(&child->mnt_child); list_move_tail(&child->mnt_hash, &mnt->mnt_hash); + } } } -- 1.9.1