1 files changed, 10 insertions, 0 deletions

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index a3f868ae3fd4..34423978b170 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -463,6 +463,14 @@ static struct inode *hugetlbfs_get_root(struct super_block *sb,
         return inode;
 }
 
+/*
+ * Hugetlbfs is not reclaimable; therefore its i_mmap_mutex will never
+ * be taken from reclaim -- unlike regular filesystems. This needs an
+ * annotation because huge_pmd_share() does an allocation under
+ * i_mmap_mutex.
+ */
+struct lock_class_key hugetlbfs_i_mmap_mutex_key;
+
 static struct inode *hugetlbfs_get_inode(struct super_block *sb,
                                         struct inode *dir,
                                         umode_t mode, dev_t dev)
@@ -474,6 +482,8 @@ static struct inode *hugetlbfs_get_inode(struct super_block *sb,
                 struct hugetlbfs_inode_info *info;
                 inode->i_ino = get_next_ino();
                 inode_init_owner(inode, dir, mode);
+                lockdep_set_class(&inode->i_mapping->i_mmap_mutex,
+                                &hugetlbfs_i_mmap_mutex_key);
                 inode->i_mapping->a_ops = &hugetlbfs_aops;
                 inode->i_mapping->backing_dev_info =&hugetlbfs_backing_dev_info;
                 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;