get rid of propagate_umount() mistakenly treating slaves as busy.

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.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2014-08-18 15:09:26 -04:00
parent 52addcf9d6
commit 88b368f27a
2 changed files with 4 additions and 1 deletions

View File

@ -1253,6 +1253,9 @@ void umount_tree(struct mount *mnt, int how)
hlist_add_head(&p->mnt_hash, &tmp_list);
}
hlist_for_each_entry(p, &tmp_list, mnt_hash)
list_del_init(&p->mnt_child);
if (how)
propagate_umount(&tmp_list);
@ -1263,7 +1266,6 @@ void umount_tree(struct mount *mnt, int how)
p->mnt_ns = NULL;
if (how < 2)
p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
list_del_init(&p->mnt_child);
if (mnt_has_parent(p)) {
put_mountpoint(p->mnt_mp);
/* move the reference to mountpoint into ->mnt_ex_mountpoint */

View File

@ -381,6 +381,7 @@ static void __propagate_umount(struct mount *mnt)
* other children
*/
if (child && list_empty(&child->mnt_mounts)) {
list_del_init(&child->mnt_child);
hlist_del_init_rcu(&child->mnt_hash);
hlist_add_before_rcu(&child->mnt_hash, &mnt->mnt_hash);
}