diff --git a/kernel_module/user/devmem.c b/kernel_module/user/devmem.c
index 483f26a..3e65e32 100644
--- a/kernel_module/user/devmem.c
+++ b/kernel_module/user/devmem.c
@@ -36,6 +36,7 @@ int main(int argc, char *argv[]) {
     }
     for (size_t i = 0; i < len; ++i) {
         printf("%02x ", (unsigned int)mem[page_offset + i]);
+        /* TODO can't edit memory? */
 		mem[page_offset + i] = i % 256;
 	}
 	puts("");