diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 799d3837e7c2..4899663996d8 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -193,6 +193,7 @@ int diUnmount(struct inode *ipimap, int mounterror)
 	 * free in-memory control structure
 	 */
 	kfree(imap);
+	JFS_IP(ipimap)->i_imap = NULL;
 
 	return (0);
 }