diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c
index 7dac21ee6ce7..3bb3b610d403 100644
--- a/fs/ceph/mdsmap.c
+++ b/fs/ceph/mdsmap.c
@@ -379,10 +379,11 @@ struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end, bool msgr2)
 		ceph_decode_skip_8(p, end, bad_ext);
 		/* required_client_features */
 		ceph_decode_skip_set(p, end, 64, bad_ext);
+		/* bal_rank_mask */
+		ceph_decode_skip_string(p, end, bad_ext);
+	}
+	if (mdsmap_ev >= 18) {
 		ceph_decode_64_safe(p, end, m->m_max_xattr_size, bad_ext);
-	} else {
-		/* This forces the usage of the (sync) SETXATTR Op */
-		m->m_max_xattr_size = 0;
 	}
 bad_ext:
 	dout("mdsmap_decode m_enabled: %d, m_damaged: %d, m_num_laggy: %d\n",
diff --git a/include/linux/ceph/mdsmap.h b/include/linux/ceph/mdsmap.h
index 4c3e0648dc27..fcc95bff72a5 100644
--- a/include/linux/ceph/mdsmap.h
+++ b/include/linux/ceph/mdsmap.h
@@ -25,7 +25,11 @@ struct ceph_mdsmap {
 	u32 m_session_timeout;          /* seconds */
 	u32 m_session_autoclose;        /* seconds */
 	u64 m_max_file_size;
-	u64 m_max_xattr_size;		/* maximum size for xattrs blob */
+	/*
+	 * maximum size for xattrs blob.
+	 * Zeroed by default to force the usage of the (sync) SETXATTR Op.
+	 */
+	u64 m_max_xattr_size;
 	u32 m_max_mds;			/* expected up:active mds number */
 	u32 m_num_active_mds;		/* actual up:active mds number */
 	u32 possible_max_rank;		/* possible max rank index */