diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index f0bc107..64ce9930 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -41,12 +41,6 @@
  * physical eraseblocks with low erase counter to free physical eraseblocks
  * with high erase counter.
  *
- * The 'ubi_wl_get_peb()' function accepts data type hints which help to pick
- * an "optimal" physical eraseblock. For example, when it is known that the
- * physical eraseblock will be "put" soon because it contains short-term data,
- * the WL sub-system may pick a free physical eraseblock with low erase
- * counter, and so forth.
- *
  * If the WL sub-system fails to erase a physical eraseblock, it marks it as
  * bad.
  *
@@ -70,8 +64,7 @@
  *    to the user; instead, we first want to let users fill them up with data;
  *
  *  o there is a chance that the user will put the physical eraseblock very
- *    soon, so it makes sense not to move it for some time, but wait; this is
- *    especially important in case of "short term" physical eraseblocks.
+ *    soon, so it makes sense not to move it for some time, but wait.
  *
  * Physical eraseblocks stay protected only for limited time. But the "time" is
  * measured in erase cycles in this case. This is implemented with help of the
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index d7cbf7a..001accc 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -814,9 +814,8 @@
 	}
 
 	/*
-	 * Garbage Collector head likely contains long-term data and
-	 * does not need to be synchronized by timer. Also GC head nodes are
-	 * not grouped.
+	 * Garbage Collector head does not need to be synchronized by timer.
+	 * Also GC head nodes are not grouped.
 	 */
 	c->jheads[GCHD].wbuf.no_timer = 1;
 	c->jheads[GCHD].grouped = 0;
diff --git a/include/mtd/ubi-user.h b/include/mtd/ubi-user.h
index 370c750..8787349 100644
--- a/include/mtd/ubi-user.h
+++ b/include/mtd/ubi-user.h
@@ -358,7 +358,17 @@
  *                             requests.
  * @lnum: logical eraseblock number to change
  * @bytes: how many bytes will be written to the logical eraseblock
+ * @dtype: pass "3" for better compatibility with old kernels
  * @padding: reserved for future, not used, has to be zeroed
+ *
+ * The @dtype field used to inform UBI about what kind of data will be written
+ * to the LEB: long term (value 1), short term (value 2), unknown (value 3).
+ * UBI tried to pick a PEB with lower erase counter for short term data and a
+ * PEB with higher erase counter for long term data. But this was not really
+ * used because users usually do not know this and could easily mislead UBI. We
+ * removed this feature in May 2012. UBI currently just ignores the @dtype
+ * field. But for better compatibility with older kernels it is recommended to
+ * set @dtype to 3 (unknown).
  */
 struct ubi_leb_change_req {
 	__s32 lnum;
@@ -369,6 +379,7 @@
 
 /**
  * struct ubi_map_req - a data structure used in map LEB requests.
+ * @dtype: pass "3" for better compatibility with old kernels
  * @lnum: logical eraseblock number to unmap
  * @padding: reserved for future, not used, has to be zeroed
  */