Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index 6fc9383..151aa95 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -1167,11 +1167,18 @@
 		if (r)
 			return r;
 
-		for (b = 0; b < from_dblock(cmd->discard_nr_blocks); b++) {
+		for (b = 0; ; b++) {
 			r = fn(context, cmd->discard_block_size, to_dblock(b),
 			       dm_bitset_cursor_get_value(&c));
 			if (r)
 				break;
+
+			if (b >= (from_dblock(cmd->discard_nr_blocks) - 1))
+				break;
+
+			r = dm_bitset_cursor_next(&c);
+			if (r)
+				break;
 		}
 
 		dm_bitset_cursor_end(&c);