How can I debug the function of malloc_in_range?

[Zhang]

Hi All,

I want to study the function malloc_in_range of the grub2.02.

So I set the followings in the grub.cfg.

serial --unit=0 --speed=115200 --word=8  --parity=no --stop=1

terminal_input serial console

terminal_output serial console

set debug=all

But when I add some  grub_printf to the function of malloc_in_range, the serial and VGA both display messy code.

So how can I debug the function of malloc_in_range