Restore -Os flag and add other sections to linker file.

payload/Makefile

@@ -3,7 +3,7 @@ OBJS = start.o payload.o
 
 CC = gcc
 OBJCOPY = objcopy
-CFLAGS = -isystem freebsd-headers/include -fno-stack-protector
+CFLAGS = -isystem freebsd-headers/include -Os -fno-stack-protector
 LDFLAGS = -T linker.x -nostdlib -nostartfiles
 
 all: $(TARGET).bin

payload/linker.x

@@ -6,7 +6,9 @@ ENTRY(_start)
 SECTIONS
 {
   . = 0x916300000;
-  .text : { *(.text) }
+  .text   : { *(.text     .text.*) }
   . = 0x916304000;
-  .data : { *(.data) }
+  .rodata : { *(.rodata   .rodata.*) }
+  .data   : { *(.data     .data.*) }
+  .bss    : { *(.bss      .bss.*) }
 }