diff options
Diffstat (limited to 'guest')
| -rw-r--r-- | guest/Makefile | 8 | ||||
| -rw-r--r-- | guest/guest.ld | 9 | ||||
| -rw-r--r-- | guest/guest16.S | 21 |
3 files changed, 38 insertions, 0 deletions
diff --git a/guest/Makefile b/guest/Makefile new file mode 100644 index 0000000..e3f1e1b --- /dev/null +++ b/guest/Makefile @@ -0,0 +1,8 @@ +guest16: guest.ld guest16.S + $(CC) $(CFLAGS) -m16 -o $@ -nostdlib -ffreestanding -Wpedantic -Wall -Wextra -Werror -T guest.ld guest16.S + +disasm: guest16 + objdump -D -b binary -m i8086 -M intel $^ + +clean: + $(RM) guest16 diff --git a/guest/guest.ld b/guest/guest.ld new file mode 100644 index 0000000..5c81da9 --- /dev/null +++ b/guest/guest.ld @@ -0,0 +1,9 @@ +OUTPUT_FORMAT(binary) + +SECTIONS { + .boot : { *(.boot) } + .text : { *(.text) } + .data : { *(.data) } + .rodata : { *(.rodata) } + /DISCARD/ : { *(.*) } +} diff --git a/guest/guest16.S b/guest/guest16.S new file mode 100644 index 0000000..7f0be0e --- /dev/null +++ b/guest/guest16.S @@ -0,0 +1,21 @@ +.code16 +.intel_syntax noprefix + +.section .boot, "ax", @progbits + // Trigger `KVM_EXIT_IO:KVM_EXIT_IO_OUT` by writing string to output port. + mov dx, 0x1000 // Output port. + lea si, [msg] // Address of string. + mov cx, [msg_len] // Len of string. + rep outsb dx, ds:[si] // Write out string bytes. + + // Trigger `KVM_EXIT_MMIO` by writing to non mapped physical address. + mov byte ptr ds:[0x2000], 0xaa + + // Trigger `KVM_EXIT_HLT`. + hlt + +.section .rodata, "a", @progbits +msg: + .asciz "Hello from Real Mode!\n" +msg_len: + .byte .-msg |