Merge branch 'post-04' into post-05

Merge branch 'post-03' into post-04
Merge branch 'post-02' into post-03
2025-12-16 14:27:49 +00:00 · 2025-09-03 17:58:33 +02:00 · 2025-09-03 17:58:33 +02:00 · 2025-09-03 17:58:28 +02:00 · 2025-09-03 17:56:38 +02:00 · 2025-09-03 17:53:14 +02:00
15 changed files with 125 additions and 421 deletions
--- a/.cargo/config.toml
+++ b/.cargo/config.toml
@@ -1,11 +1,9 @@
 [unstable]
-# build-std = ["core", "compiler_builtins"]
+build-std = ["core", "compiler_builtins"]
+build-std-features = ["compiler-builtins-mem"]

 [build]
-# target = "x86_64-blog_os.json"
+target = "x86_64-blog_os.json"

 [target.'cfg(target_os = "none")']
-runner = "cargo run --manifest-path disk_image/Cargo.toml --bin runner --quiet"
-
-[alias]
-bootimage = "run --manifest-path disk_image/Cargo.toml --bin disk_image --quiet"
+runner = "bootimage runner"
--- a/.github/workflows/build-code.yml
+++ b/.github/workflows/build-code.yml
@@ -1,4 +1,4 @@
-name: Build Code
+name: Code

 on:
  push:
@@ -16,6 +16,7 @@ jobs:
  check:
    name: Check
    strategy:
+      fail-fast: false
      matrix:
        platform: [
          ubuntu-latest,
@@ -41,6 +42,7 @@ jobs:
  test:
    name: Test
    strategy:
+      fail-fast: false
      matrix:
        platform: [
          ubuntu-latest,
@@ -76,14 +78,10 @@ jobs:
          HOMEBREW_NO_AUTO_UPDATE: 1
          HOMEBREW_NO_BOTTLE_SOURCE_FALLBACK: 1
          HOMEBREW_NO_INSTALL_CLEANUP: 1
-      - name: Install Scoop (Windows)
-        run: |
-          Invoke-Expression (New-Object System.Net.WebClient).DownloadString('https://get.scoop.sh')
-          echo ::add-path::$HOME\scoop\shims
-        if: runner.os == 'Windows'
-        shell: pwsh
      - name: Install QEMU (Windows)
-        run: scoop install qemu
+        run: |
+          choco install qemu --version 2021.5.5
+          echo "$Env:Programfiles\qemu" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
        if: runner.os == 'Windows'
        shell: pwsh
      - name: "Print QEMU Version"
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,22 +1,24 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-[[package]]
-name = "anyhow"
-version = "1.0.32"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6b602bfe940d21c130f3895acd65221e8a61270debe89d628b9cb4e3ccb8569b"
+version = 4

 [[package]]
 name = "bit_field"
-version = "0.9.0"
+version = "0.10.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed8765909f9009617974ab6b7d332625b320b33c326b1e9321382ef1999b5d56"
+checksum = "dc827186963e592360843fb5ba4b973e145841266c1357f7180c43526f2e5b61"

 [[package]]
 name = "bitflags"
-version = "1.2.1"
+version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
+checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
+
+[[package]]
+name = "bitflags"
+version = "2.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a65b545ab31d687cff52899d4890855fec459eb6afe0da6417b8a18da87aa29"

 [[package]]
 name = "blog_os"
@@ -24,168 +26,32 @@ version = "0.1.0"
 dependencies = [
 "bootloader",
 "lazy_static",
- "rlibc",
- "spin",
+ "spin 0.5.2",
 "uart_16550",
- "volatile",
+ "volatile 0.2.7",
 "x86_64",
 ]

 [[package]]
 name = "bootloader"
-version = "0.9.8"
-
-[[package]]
-name = "bootloader-locator"
-version = "0.0.3"
-dependencies = [
- "cargo_metadata",
- "locate-cargo-manifest",
- "thiserror",
-]
-
-[[package]]
-name = "cargo_metadata"
-version = "0.11.1"
+version = "0.9.33"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "89fec17b16f1ac67908af82e47d0a90a7afd0e1827b181cd77504323d3263d35"
-dependencies = [
- "semver",
- "serde",
- "serde_json",
-]
-
-[[package]]
-name = "disk_image"
-version = "0.1.0"
-dependencies = [
- "anyhow",
- "bootloader-locator",
- "locate-cargo-manifest",
- "runner-utils",
-]
-
-[[package]]
-name = "itoa"
-version = "0.4.6"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc6f3ad7b9d11a0c00842ff8de1b60ee58661048eb8049ed33c73594f359d7e6"
-
-[[package]]
-name = "json"
-version = "0.12.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "078e285eafdfb6c4b434e0d31e8cfcb5115b651496faca5749b88fafd4f23bfd"
+checksum = "7bdfddac270bbdd45903296bc1caf29a7fdce6b326aaf0bbab7f04c5f98b7447"

 [[package]]
 name = "lazy_static"
-version = "1.4.0"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
 dependencies = [
- "spin",
+ "spin 0.9.8",
 ]

 [[package]]
-name = "libc"
-version = "0.2.76"
+name = "rustversion"
+version = "1.0.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "755456fae044e6fa1ebbbd1b3e902ae19e73097ed4ed87bb79934a867c007bc3"
-
-[[package]]
-name = "locate-cargo-manifest"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d264d672563b20c0a2eb9045f4072e1352002f6c316cc0677bed8b767e17b7e1"
-dependencies = [
- "json",
- "thiserror",
-]
-
-[[package]]
-name = "proc-macro2"
-version = "1.0.19"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04f5f085b5d71e2188cb8271e5da0161ad52c3f227a661a3c135fdf28e258b12"
-dependencies = [
- "unicode-xid",
-]
-
-[[package]]
-name = "quote"
-version = "1.0.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aa563d17ecb180e500da1cfd2b028310ac758de548efdd203e18f283af693f37"
-dependencies = [
- "proc-macro2",
-]
-
-[[package]]
-name = "rlibc"
-version = "1.0.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fc874b127765f014d792f16763a81245ab80500e2ad921ed4ee9e82481ee08fe"
-
-[[package]]
-name = "runner-utils"
-version = "0.0.2"
-dependencies = [
- "thiserror",
- "wait-timeout",
-]
-
-[[package]]
-name = "ryu"
-version = "1.0.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "71d301d4193d031abdd79ff7e3dd721168a9572ef3fe51a1517aba235bd8f86e"
-
-[[package]]
-name = "semver"
-version = "0.10.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "394cec28fa623e00903caf7ba4fa6fb9a0e260280bb8cdbbba029611108a0190"
-dependencies = [
- "semver-parser",
- "serde",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.7.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
-
-[[package]]
-name = "serde"
-version = "1.0.115"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e54c9a88f2da7238af84b5101443f0c0d0a3bbdc455e34a5c9497b1903ed55d5"
-dependencies = [
- "serde_derive",
-]
-
-[[package]]
-name = "serde_derive"
-version = "1.0.115"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "609feed1d0a73cc36a0182a840a9b37b4a82f0b1150369f0536a9e3f2a31dc48"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "serde_json"
-version = "1.0.57"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "164eacbdb13512ec2745fb09d51fd5b22b0d65ed294a1dcf7285a360c80a675c"
-dependencies = [
- "itoa",
- "ryu",
- "serde",
-]
+checksum = "b39cdef0fa800fc44525c84ccb54a029961a8215f9619753635a9c0d2538d46d"

 [[package]]
 name = "spin"
@@ -194,73 +60,42 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"

 [[package]]
-name = "syn"
-version = "1.0.39"
+name = "spin"
+version = "0.9.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "891d8d6567fe7c7f8835a3a98af4208f3846fba258c1bc3c31d6e506239f11f9"
-dependencies = [
- "proc-macro2",
- "quote",
- "unicode-xid",
-]
-
-[[package]]
-name = "thiserror"
-version = "1.0.20"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7dfdd070ccd8ccb78f4ad66bf1982dc37f620ef696c6b5028fe2ed83dd3d0d08"
-dependencies = [
- "thiserror-impl",
-]
-
-[[package]]
-name = "thiserror-impl"
-version = "1.0.20"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd80fc12f73063ac132ac92aceea36734f04a1d93c1240c6944e23a3b8841793"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
+checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"

 [[package]]
 name = "uart_16550"
-version = "0.2.7"
+version = "0.2.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e58fc40dc1712664fc9b0a7bd8ca2f21ab49960924fb245a80a05e1e92f3dfe9"
+checksum = "614ff2a87880d4bd4374722268598a970bbad05ced8bf630439417347254ab2e"
 dependencies = [
- "bitflags",
+ "bitflags 1.3.2",
+ "rustversion",
 "x86_64",
 ]

 [[package]]
-name = "unicode-xid"
-version = "0.2.1"
+name = "volatile"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7fe0bb3479651439c9112f72b6c505038574c9fbb575ed1bf3b797fa39dd564"
+checksum = "f6b06ad3ed06fef1713569d547cdbdb439eafed76341820fb0e0344f29a41945"

 [[package]]
 name = "volatile"
-version = "0.4.0-alpha.00"
+version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a1da81878b88e2b57ca8b3d62c0c3e9979d9531cfe0e6d1c094174d8458eac6"
-
-[[package]]
-name = "wait-timeout"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f200f5b12eb75f8c1ed65abd4b2db8a6e1b138a20de009dacee265a2498f3f6"
-dependencies = [
- "libc",
-]
+checksum = "442887c63f2c839b346c192d047a7c87e73d0689c9157b00b53dcc27dd5ea793"

 [[package]]
 name = "x86_64"
-version = "0.11.0"
+version = "0.14.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "365de37eb7c6da582cbb510dd0f3f1235d24ff6309a8a96e8a9909cc9bfd608f"
+checksum = "c101112411baafbb4bf8d33e4c4a80ab5b02d74d2612331c61e8192fc9710491"
 dependencies = [
 "bit_field",
- "bitflags",
+ "bitflags 2.9.2",
+ "rustversion",
+ "volatile 0.4.6",
 ]
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,33 +2,36 @@
 name = "blog_os"
 version = "0.1.0"
 authors = ["Philipp Oppermann <dev@phil-opp.com>"]
-edition = "2018"
-
-[workspace]
-members = [
-    "disk_image",
-]
+edition = "2024"

 [[test]]
 name = "should_panic"
 harness = false

 [dependencies]
-bootloader = { path = "../../uefi-test"}
-rlibc = "1.0.0"
-volatile = "0.4.0-alpha"
+bootloader = "0.9"
+volatile = "0.2.6"
 spin = "0.5.2"
-x86_64 = "0.11.0"
+x86_64 = "0.14.2"
 uart_16550 = "0.2.0"

 [dependencies.lazy_static]
 version = "1.0"
 features = ["spin_no_std"]

+[[bin]]
+name = "blog_os"
+test = true
+bench = false
+

 [package.metadata.bootimage]
 test-args = [
-    "-device", "isa-debug-exit,iobase=0xf4,iosize=0x04", "-serial", "stdio",
-    "-display", "none"
+    "-device",
+    "isa-debug-exit,iobase=0xf4,iosize=0x04",
+    "-serial",
+    "stdio",
+    "-display",
+    "none",
 ]
-test-success-exit-code = 33         # (0x10 << 1) | 1
+test-success-exit-code = 33 # (0x10 << 1) | 1
--- a/README.md
+++ b/README.md
@@ -1,10 +1,10 @@
-# Blog OS (Testing)
+# Blog OS (CPU Exceptions)

-[![Build Status](https://github.com/phil-opp/blog_os/workflows/Build%20Code/badge.svg?branch=post-04)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Build+Code%22+branch%3Apost-04)
+[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-05)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-05)

-This repository contains the source code for the [Testing][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.
+This repository contains the source code for the [CPU Exceptions][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.

-[post]: https://os.phil-opp.com/testing/
+[post]: https://os.phil-opp.com/cpu-exceptions/

 **Check out the [master branch](https://github.com/phil-opp/blog_os) for more information.**

--- a/disk_image/Cargo.toml
+++ b/disk_image/Cargo.toml
@@ -1,13 +0,0 @@
-[package]
-name = "disk_image"
-version = "0.1.0"
-authors = ["Philipp Oppermann <dev@phil-opp.com>"]
-edition = "2018"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-anyhow = "1.0.32"
-bootloader-locator = {path = "../../../bootloader-locator"}
-runner-utils = { path = "../../../runner-utils/" }
-locate-cargo-manifest = "0.2.0"
--- a/disk_image/src/bin/runner.rs
+++ b/disk_image/src/bin/runner.rs
@@ -1,57 +0,0 @@
-use anyhow::anyhow;
-use std::{
-    path::PathBuf,
-    process::{Command, ExitStatus},
-    time::Duration,
-};
-
-const RUN_ARGS: &[&str] = &["-d", "int", "--no-reboot", "-s"];
-const TEST_ARGS: &[&str] = &[
-    "-device",
-    "isa-debug-exit,iobase=0xf4,iosize=0x04",
-    "-serial",
-    "stdio",
-    "-display",
-    "none",
-    "--no-reboot",
-];
-const TEST_TIMEOUT_SECS: u64 = 10;
-
-fn main() -> anyhow::Result<()> {
-    let kernel_binary_path = {
-        let path = PathBuf::from(std::env::args().nth(1).unwrap());
-        path.canonicalize()?
-    };
-
-    let disk_image = disk_image::create_disk_image(&kernel_binary_path, true)?;
-
-    let mut run_cmd = Command::new("qemu-system-x86_64");
-    run_cmd
-        .arg("-drive")
-        .arg(format!("format=raw,file={}", disk_image.display()));
-
-    let binary_kind = runner_utils::binary_kind(&kernel_binary_path);
-    if binary_kind.is_test() {
-        run_cmd.args(TEST_ARGS);
-
-        let exit_status = run_test_command(run_cmd)?;
-        match exit_status.code() {
-            Some(33) => {} // success
-            other => return Err(anyhow!("Test failed (exit code: {:?})", other)),
-        }
-    } else {
-        run_cmd.args(RUN_ARGS);
-
-        let exit_status = run_cmd.status()?;
-        if !exit_status.success() {
-            std::process::exit(exit_status.code().unwrap_or(1));
-        }
-    }
-
-    Ok(())
-}
-
-fn run_test_command(mut cmd: Command) -> anyhow::Result<ExitStatus> {
-    let status = runner_utils::run_with_timeout(&mut cmd, Duration::from_secs(TEST_TIMEOUT_SECS))?;
-    Ok(status)
-}
--- a/disk_image/src/lib.rs
+++ b/disk_image/src/lib.rs
@@ -1,45 +0,0 @@
-use anyhow::anyhow;
-use std::{
-    path::{Path, PathBuf},
-    process::Command,
-};
-
-pub fn create_disk_image(kernel_binary_path: &Path, bios_only: bool) -> anyhow::Result<PathBuf> {
-    let bootloader_info = bootloader_locator::locate_bootloader()?;
-    let kernel_manifest_path = &bootloader_info.kernel_manifest_path;
-
-    let mut build_cmd = Command::new(env!("CARGO"));
-    build_cmd.current_dir(bootloader_info.package.manifest_path.parent().unwrap());
-    build_cmd.arg("builder");
-    build_cmd
-        .arg("--kernel-manifest")
-        .arg(&kernel_manifest_path);
-    build_cmd.arg("--kernel-binary").arg(&kernel_binary_path);
-    build_cmd
-        .arg("--target-dir")
-        .arg(kernel_manifest_path.parent().unwrap().join("target"));
-    build_cmd
-        .arg("--out-dir")
-        .arg(kernel_binary_path.parent().unwrap());
-    build_cmd.arg("--quiet");
-    if bios_only {
-        build_cmd.arg("--firmware").arg("bios");
-    }
-
-    if !build_cmd.status()?.success() {
-        return Err(anyhow!("build failed"));
-    }
-
-    let kernel_binary_name = kernel_binary_path.file_name().unwrap().to_str().unwrap();
-    let disk_image = kernel_binary_path
-        .parent()
-        .unwrap()
-        .join(format!("bootimage-bios-{}.bin", kernel_binary_name));
-    if !disk_image.exists() {
-        return Err(anyhow!(
-            "Disk image does not exist at {} after bootloader build",
-            disk_image.display()
-        ));
-    }
-    Ok(disk_image)
-}
--- a/disk_image/src/main.rs
+++ b/disk_image/src/main.rs
@@ -1,40 +0,0 @@
-use anyhow::anyhow;
-use std::process::Command;
-
-const TARGET_NAME: &str = "x86_64-blog_os";
-const KERNEL_BINARIES: &[&str] = &["blog_os"];
-
-fn main() -> anyhow::Result<()> {
-    // build all binaries
-    let mut build_cmd = Command::new(env!("CARGO"));
-    build_cmd.arg("build");
-    build_cmd.arg("--release");
-    build_cmd.arg("-Zbuild-std=core");
-    build_cmd
-        .arg("--target")
-        .arg(format!("{}.json", TARGET_NAME));
-    if !build_cmd.status()?.success() {
-        return Err(anyhow!("build failed"));
-    };
-
-    let kernel_manifest = locate_cargo_manifest::locate_manifest()?;
-    let target_dir_root = kernel_manifest.parent().unwrap().join("target");
-    let target_dir = target_dir_root.join(TARGET_NAME).join("release");
-
-    for binary_name in KERNEL_BINARIES {
-        let binary_path = {
-            let path = target_dir.join(binary_name);
-            path.canonicalize()?
-        };
-
-        let disk_image = disk_image::create_disk_image(&binary_path, false)?;
-
-        println!(
-            "Created disk image for binary {} at {}",
-            binary_name,
-            disk_image.display()
-        );
-    }
-
-    Ok(())
-}
--- a/src/interrupts.rs
+++ b/src/interrupts.rs
@@ -0,0 +1,25 @@
+use crate::println;
+use lazy_static::lazy_static;
+use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
+
+lazy_static! {
+    static ref IDT: InterruptDescriptorTable = {
+        let mut idt = InterruptDescriptorTable::new();
+        idt.breakpoint.set_handler_fn(breakpoint_handler);
+        idt
+    };
+}
+
+pub fn init_idt() {
+    IDT.load();
+}
+
+extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
+    println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
+}
+
+#[test_case]
+fn test_breakpoint_exception() {
+    // invoke a breakpoint exception
+    x86_64::instructions::interrupts::int3();
+}
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,16 +1,19 @@
 #![no_std]
 #![cfg_attr(test, no_main)]
 #![feature(custom_test_frameworks)]
+#![feature(abi_x86_interrupt)]
 #![test_runner(crate::test_runner)]
 #![reexport_test_harness_main = "test_main"]

-extern crate rlibc;
-
 use core::panic::PanicInfo;

+pub mod interrupts;
 pub mod serial;
-//pub mod vga_buffer;
+pub mod vga_buffer;

+pub fn init() {
+    interrupts::init_idt();
+}
 pub trait Testable {
    fn run(&self) -> ();
 }
@@ -59,8 +62,9 @@ pub fn exit_qemu(exit_code: QemuExitCode) {

 /// Entry point for `cargo xtest`
 #[cfg(test)]
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
+    init();
    test_main();
    loop {}
 }
--- a/src/main.rs
+++ b/src/main.rs
@@ -4,36 +4,30 @@
 #![test_runner(blog_os::test_runner)]
 #![reexport_test_harness_main = "test_main"]

-use blog_os::serial_println;
-use core::{panic::PanicInfo, ptr, slice};
+use blog_os::println;
+use core::panic::PanicInfo;
+
+#[unsafe(no_mangle)]
+pub extern "C" fn _start() -> ! {
+    println!("Hello World{}", "!");
+
+    blog_os::init();
+
+    // invoke a breakpoint exception
+    x86_64::instructions::interrupts::int3();

-#[no_mangle]
-pub extern "C" fn _start(boot_info: &'static mut bootloader::boot_info::BootInfo) -> ! {
    #[cfg(test)]
    test_main();

-    let mut framebuffer = {
-        let ptr = boot_info.framebuffer.start_addr as *mut u8;
-        let slice = unsafe { slice::from_raw_parts_mut(ptr, boot_info.framebuffer.len) };
-        volatile::Volatile::new(slice)
-    };
-
-    //serial_println!("Hello World{}", "!");
-
-    for i in 0..boot_info.framebuffer.len {
-        framebuffer.index_mut(i).write(0x99);
-    }
-
-    loop {
-        x86_64::instructions::hlt();
-    }
+    println!("It did not crash!");
+    loop {}
 }

 /// This function is called on panic.
 #[cfg(not(test))]
 #[panic_handler]
 fn panic(info: &PanicInfo) -> ! {
-    serial_println!("{}", info);
+    println!("{}", info);
    loop {}
 }

--- a/tests/basic_boot.rs
+++ b/tests/basic_boot.rs
@@ -4,9 +4,10 @@
 #![test_runner(blog_os::test_runner)]
 #![reexport_test_harness_main = "test_main"]

+use blog_os::println;
 use core::panic::PanicInfo;

-#[no_mangle] // don't mangle the name of this function
+#[unsafe(no_mangle)] // don't mangle the name of this function
 pub extern "C" fn _start() -> ! {
    test_main();

@@ -20,5 +21,5 @@ fn panic(info: &PanicInfo) -> ! {

 #[test_case]
 fn test_println() {
-    //println!("test_println output");
+    println!("test_println output");
 }
--- a/tests/should_panic.rs
+++ b/tests/should_panic.rs
@@ -1,10 +1,10 @@
 #![no_std]
 #![no_main]

-use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
 use core::panic::PanicInfo;

-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
    should_fail();
    serial_println!("[test did not panic]");
--- a/x86_64-blog_os.json
+++ b/x86_64-blog_os.json
@@ -1,15 +1,16 @@
 {
    "llvm-target": "x86_64-unknown-none",
-    "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
+    "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128",
    "arch": "x86_64",
    "target-endian": "little",
-    "target-pointer-width": "64",
-    "target-c-int-width": "32",
+    "target-pointer-width": 64,
+    "target-c-int-width": 32,
    "os": "none",
    "executables": true,
    "linker-flavor": "ld.lld",
    "linker": "rust-lld",
    "panic-strategy": "abort",
    "disable-redzone": true,
-    "features": "-mmx,-sse,+soft-float"
+    "features": "-mmx,-sse,+soft-float",
+    "rustc-abi": "x86-softfloat"
  }