--- x/block/bdev.c
+++ y/block/bdev.c
@@ -88,7 +88,9 @@ static void kill_bdev(struct block_devic
 		return;
 
 	invalidate_bh_lrus();
+	filemap_invalidate_lock(mapping);
 	truncate_inode_pages(mapping, 0);
+	filemap_invalidate_unlock(mapping);
 }
 
 /* Invalidate clean unused buffers and pagecache. */