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equation314equation314
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Step 5: run a complex guest OS
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Lines changed: 327 additions & 83 deletions

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‎.gitmodules‎

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@@ -0,0 +1,3 @@
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[submodule "guest/nimbos"]
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path = guest/nimbos
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url = https://github.com/equation314/nimbos.git

‎README.md‎

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@@ -10,6 +10,24 @@ Install [cargo-binutils](https://github.com/rust-embedded/cargo-binutils) to use
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$ cargo install cargo-binutils
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```
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Your also need to install [musl-gcc](http://musl.cc/x86_64-linux-musl-cross.tgz) to build guest user applications.
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## Build Guest OS
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```console
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$ git submodule init && git submodule update
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$ cd guest/nimbos/kernel
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$ make user
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$ make GUEST=on
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```
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## Build Guest BIOS
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```console
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$ cd guest/bios
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$ make
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```
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## Build & Run Hypervisor
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```console
@@ -33,4 +51,22 @@ arch = x86_64
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build_mode = release
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log_level = info
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......
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Running guest...
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NN NN iii bb OOOOO SSSSS
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NNN NN mm mm mmmm bb OO OO SS
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NN N NN iii mmm mm mm bbbbbb OO OO SSSSS
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NN NNN iii mmm mm mm bb bb OO OO SS
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NN NN iii mmm mm mm bbbbbb OOOO0 SSSSS
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___ ____ ___ ___
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|__ \ / __ \ |__ \ |__ \
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__/ / / / / / __/ / __/ /
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/ __/ / /_/ / / __/ / __/
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/____/ \____/ /____/ /____/
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arch = x86_64
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platform = rvm-guest-x86_64
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build_mode = release
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log_level = warn
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......
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```

‎guest/bios/.gitignore‎

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out/

‎guest/bios/Makefile‎

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OUT ?= out
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SRC := boot16.S
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ldscript := rvm-bios.lds
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target := $(OUT)/rvm-bios
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target-obj := $(target).o
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target-elf := $(target).elf
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target-bin := $(target).bin
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target-disasm := $(target).asm
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AS ?= as
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LD ?= ld
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OBJCOPY ?= objcopy
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OBJDUMP ?= objdump
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all: $(OUT) $(target).bin
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disasm:
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$(OBJDUMP) -d -m i8086 -M intel $(target).elf | less
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$(OUT):
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mkdir -p $(OUT)
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$(target-obj): $(SRC)
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$(AS) --32 -msyntax=intel -mnaked-reg $< -o $@
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$(target-elf): $(target-obj) $(ldscript)
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$(LD) -T$(ldscript) $< -o $@
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$(OBJDUMP) -d -m i8086 -M intel $@ > $(target-disasm)
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$(target-bin): $(target-elf)
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$(OBJCOPY) $< --strip-all -O binary $@
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clean:
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rm -rf $(OUT)
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.PHONY: all disasm clean

‎guest/bios/boot16.S‎

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.section .text
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.code16
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.global entry16
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entry16:
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cli
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cld
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xor ax, ax
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mov ds, ax
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mov es, ax
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mov ss, ax
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lgdt [prot_gdt_desc]
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mov eax, cr0
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or eax, 0x1
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mov cr0, eax
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ljmp 0x8, entry32
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.code32
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.global entry32
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entry32:
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mov ax, 0x10
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mov ds, ax
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mov es, ax
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mov ss, ax
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mov fs, ax
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mov gs, ax
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mov esp, 0x7000 # temporary stack
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mov ecx, 0x200000 # kernel entry
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mov eax, 0x1BADB002 # multiboot magic
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mov ebx, 0 # multiboot information (unsupported)
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jmp ecx
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.balign 16
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prot_gdt:
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.quad 0x0000000000000000 # 0x00: null
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.quad 0x00cf9b000000ffff # 0x08: code segment (base=0, limit=0xfffff, type=32bit code exec/read, DPL=0, 4k)
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.quad 0x00cf93000000ffff # 0x18: data segment (base=0, limit=0xfffff, type=32bit data read/write, DPL=0, 4k)
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prot_gdt_desc:
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.short prot_gdt_desc - prot_gdt - 1 # limit
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.long prot_gdt # base

‎guest/bios/rvm-bios.lds‎

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@@ -0,0 +1,16 @@
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OUTPUT_ARCH(i386)
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BASE_ADDRESS = 0x8000;
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ENTRY(entry16)
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SECTIONS
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{
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. = BASE_ADDRESS;
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.text : {
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*(.text .text.*)
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}
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/DISCARD/ : {
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*(.eh_frame) *(.eh_frame_hdr)
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}
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}

‎guest/nimbos‎

Submodule nimbos added at 545ab80

‎hypervisor/Makefile‎

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Original file line numberDiff line numberDiff line change
@@ -3,6 +3,9 @@ ARCH ?= x86_64
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MODE ?= release
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LOG ?= warn
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6+
BIOS_IMG ?= ../guest/bios/out/rvm-bios.bin
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GUEST_IMG ?= ../guest/nimbos/kernel/target/x86_64/release/nimbos.bin
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export ARCH
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export MODE
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export LOG
@@ -25,7 +28,9 @@ GDB := gdb-multiarch
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qemu := qemu-system-$(ARCH)
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qemu_args := -nographic -m 128M
2730

28-
qemu_args += -cpu host,+x2apic,+vmx -accel kvm
31+
qemu_args += -cpu host,+x2apic,+vmx -accel kvm \
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-device loader,addr=0x4000000,file=$(BIOS_IMG),force-raw=on \
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-device loader,addr=0x4001000,file=$(GUEST_IMG),force-raw=on
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3035
ifeq ($(ARCH), x86_64)
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qemu_args += \

‎hypervisor/src/hv/gconfig.rs‎

Lines changed: 9 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -1,9 +1,12 @@
1-
use rvm::GuestPhysAddr;
1+
use rvm::{GuestPhysAddr, HostPhysAddr};
2+
3+
pub const BIOS_PADDR: HostPhysAddr = 0x400_0000;
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pub const BIOS_SIZE: usize = 0x1000;
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6+
pub const GUEST_IMAGE_PADDR: HostPhysAddr = 0x400_1000;
7+
pub const GUEST_IMAGE_SIZE: usize = 0x10_0000; // 1M
28

39
pub const GUEST_PHYS_MEMORY_BASE: GuestPhysAddr = 0;
10+
pub const BIOS_ENTRY: GuestPhysAddr = 0x8000;
11+
pub const GUEST_ENTRY: GuestPhysAddr = 0x20_0000;
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pub const GUEST_PHYS_MEMORY_SIZE: usize = 0x100_0000; // 16M
5-
6-
pub const GUEST_PT1: GuestPhysAddr = 0x1000;
7-
pub const GUEST_PT2: GuestPhysAddr = 0x2000;
8-
pub const GUEST_ENTRY: GuestPhysAddr = 0x8000;
9-
pub const GUEST_STACK_TOP: GuestPhysAddr = 0x7000;

‎hypervisor/src/hv/mod.rs‎

Lines changed: 42 additions & 51 deletions
Original file line numberDiff line numberDiff line change
@@ -3,12 +3,12 @@ mod gpm;
33
mod hal;
44
mod vmexit;
55

6-
use rvm::{GuestPhysAddr, HostVirtAddr, MemFlags, RvmPerCpu, RvmResult};
6+
use rvm::{GuestPhysAddr, HostPhysAddr, HostVirtAddr, MemFlags, RvmPerCpu, RvmResult};
77

88
use self::gconfig::*;
99
use self::gpm::{GuestMemoryRegion, GuestPhysMemorySet};
1010
use self::hal::RvmHalImpl;
11-
use crate::mm::address::virt_to_phys;
11+
use crate::mm::address::{phys_to_virt, virt_to_phys};
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1313
#[repr(align(4096))]
1414
struct AlignedMemory<const LEN: usize>([u8; LEN]);
@@ -22,42 +22,51 @@ fn gpa_as_mut_ptr(guest_paddr: GuestPhysAddr) -> *mut u8 {
2222
host_vaddr as *mut u8
2323
}
2424

25-
fn setup_guest_page_table() {
26-
use x86_64::structures::paging::{PageTable, PageTableFlags as PTF};
27-
let pt1 = unsafe { &mut *(gpa_as_mut_ptr(GUEST_PT1) as *mut PageTable) };
28-
let pt2 = unsafe { &mut *(gpa_as_mut_ptr(GUEST_PT2) as *mut PageTable) };
29-
// identity mapping
30-
pt1[0].set_addr(
31-
x86_64::PhysAddr::new(GUEST_PT2 as _),
32-
PTF::PRESENT | PTF::WRITABLE,
33-
);
34-
pt2[0].set_addr(
35-
x86_64::PhysAddr::new(0),
36-
PTF::PRESENT | PTF::WRITABLE | PTF::HUGE_PAGE,
37-
);
25+
fn load_guest_image(hpa: HostPhysAddr, load_gpa: GuestPhysAddr, size: usize) {
26+
let image_ptr = phys_to_virt(hpa) as *const u8;
27+
let image = unsafe { core::slice::from_raw_parts(image_ptr, size) };
28+
unsafe {
29+
core::slice::from_raw_parts_mut(gpa_as_mut_ptr(load_gpa), size).copy_from_slice(image)
30+
}
3831
}
3932

4033
fn setup_gpm() -> RvmResult<GuestPhysMemorySet> {
41-
setup_guest_page_table();
42-
43-
// copy guest code
44-
unsafe {
45-
core::ptr::copy_nonoverlapping(
46-
test_guest as usize as *const u8,
47-
gpa_as_mut_ptr(GUEST_ENTRY),
48-
0x100,
49-
);
50-
}
34+
// copy BIOS and guest images
35+
load_guest_image(BIOS_PADDR, BIOS_ENTRY, BIOS_SIZE);
36+
load_guest_image(GUEST_IMAGE_PADDR, GUEST_ENTRY, GUEST_IMAGE_SIZE);
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5238
// create nested page table and add mapping
5339
let mut gpm = GuestPhysMemorySet::new()?;
54-
let guest_memory_regions = [GuestMemoryRegion {
55-
// RAM
56-
gpa: GUEST_PHYS_MEMORY_BASE,
57-
hpa: virt_to_phys(gpa_as_mut_ptr(GUEST_PHYS_MEMORY_BASE) as HostVirtAddr),
58-
size: GUEST_PHYS_MEMORY_SIZE,
59-
flags: MemFlags::READ | MemFlags::WRITE | MemFlags::EXECUTE,
60-
}];
40+
let guest_memory_regions = [
41+
GuestMemoryRegion {
42+
// RAM
43+
gpa: GUEST_PHYS_MEMORY_BASE,
44+
hpa: virt_to_phys(gpa_as_mut_ptr(GUEST_PHYS_MEMORY_BASE) as HostVirtAddr),
45+
size: GUEST_PHYS_MEMORY_SIZE,
46+
flags: MemFlags::READ | MemFlags::WRITE | MemFlags::EXECUTE,
47+
},
48+
GuestMemoryRegion {
49+
// IO APIC
50+
gpa: 0xfec0_0000,
51+
hpa: 0xfec0_0000,
52+
size: 0x1000,
53+
flags: MemFlags::READ | MemFlags::WRITE | MemFlags::DEVICE,
54+
},
55+
GuestMemoryRegion {
56+
// HPET
57+
gpa: 0xfed0_0000,
58+
hpa: 0xfed0_0000,
59+
size: 0x1000,
60+
flags: MemFlags::READ | MemFlags::WRITE | MemFlags::DEVICE,
61+
},
62+
GuestMemoryRegion {
63+
// Local APIC
64+
gpa: 0xfee0_0000,
65+
hpa: 0xfee0_0000,
66+
size: 0x1000,
67+
flags: MemFlags::READ | MemFlags::WRITE | MemFlags::DEVICE,
68+
},
69+
];
6170
for r in guest_memory_regions.into_iter() {
6271
gpm.map_region(r.into())?;
6372
}
@@ -75,27 +84,9 @@ pub fn run() -> ! {
7584
info!("{:#x?}", gpm);
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7786
let mut vcpu = percpu
78-
.create_vcpu(GUEST_ENTRY, gpm.nest_page_table_root())
87+
.create_vcpu(BIOS_ENTRY, gpm.nest_page_table_root())
7988
.unwrap();
80-
vcpu.set_page_table_root(GUEST_PT1);
81-
vcpu.set_stack_pointer(GUEST_STACK_TOP);
82-
info!("{:#x?}", vcpu);
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8490
println!("Running guest...");
8591
vcpu.run();
8692
}
87-
88-
unsafe extern "C" fn test_guest() -> ! {
89-
for i in 0..100 {
90-
core::arch::asm!(
91-
"vmcall",
92-
inout("rax") i => _,
93-
in("rdi") 2,
94-
in("rsi") 3,
95-
in("rdx") 3,
96-
in("rcx") 3,
97-
);
98-
}
99-
core::arch::asm!("mov qword ptr [$0xffff233], $2333"); // panic
100-
loop {}
101-
}

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