diff --git a/fs/nfs/getroot.c b/fs/nfs/getroot.c index 0ee43843f4ec40c79f1516fb869a5eb720cb355c..e6242cdbaf9198147d9b5225ac08cc8df630b001 100644 --- a/fs/nfs/getroot.c +++ b/fs/nfs/getroot.c @@ -57,6 +57,17 @@ static int nfs_superblock_set_dummy_root(struct super_block *sb, struct inode *i } /* Circumvent igrab(): we know the inode is not being freed */ atomic_inc(&inode->i_count); + /* + * Ensure that this dentry is invisible to d_find_alias(). + * Otherwise, it may be spliced into the tree by + * d_materialise_unique if a parent directory from the same + * filesystem gets mounted at a later time. + * This again causes shrink_dcache_for_umount_subtree() to + * Oops, since the test for IS_ROOT() will fail. + */ + spin_lock(&dcache_lock); + list_del_init(&sb->s_root->d_alias); + spin_unlock(&dcache_lock); } return 0; }