diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index ae12696ec492c67339409904bb612e9fdc372689..d95da0b2bc418dfce01d60cbac8c8144c1f70f25 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -63,6 +63,9 @@ enum wb_reason {
 struct wb_completion {
 	atomic_t		cnt;
 	wait_queue_head_t	*waitq;
+
+	KABI_RESERVE(1)
+	KABI_RESERVE(2)
 };
 
 #define __WB_COMPLETION_INIT(_waitq)	\
@@ -160,6 +163,13 @@ struct bdi_writeback {
 		struct rcu_head rcu;
 	};
 #endif
+
+	KABI_RESERVE(1)
+	KABI_RESERVE(2)
+	KABI_RESERVE(3)
+	KABI_RESERVE(4)
+	KABI_RESERVE(5)
+	KABI_RESERVE(6)
 };
 
 struct backing_dev_info {
@@ -198,6 +208,11 @@ struct backing_dev_info {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *debug_dir;
 #endif
+
+	KABI_RESERVE(1)
+	KABI_RESERVE(2)
+	KABI_RESERVE(3)
+	KABI_RESERVE(4)
 };
 
 struct wb_lock_cookie {
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 083387c00f0c8b8e070705c38da59c97c8170dcb..447662e1d76f62a084a1bb009e65d9be5a3782dc 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -89,6 +89,10 @@ struct writeback_control {
 	size_t wb_lcand_bytes;		/* bytes written by last candidate */
 	size_t wb_tcand_bytes;		/* bytes written by this candidate */
 #endif
+
+	KABI_RESERVE(1)
+	KABI_RESERVE(2)
+	KABI_RESERVE(3)
 };
 
 static inline blk_opf_t wbc_to_write_flags(struct writeback_control *wbc)