Merge branch 'post-08' into post-09

Required since Rust 2024 edition

.cargo/config.toml

@@ -1,3 +1,7 @@
+[unstable]
+build-std = ["core", "compiler_builtins"]
+build-std-features = ["compiler-builtins-mem"]
+
 [build]
 target = "x86_64-blog_os.json"
 

.github/workflows/build-code.yml

@@ -1,96 +0,0 @@
-name: Build Code
-
-on:
-  push:
-    branches:
-      - '*'
-      - '!staging.tmp'
-    tags:
-      - '*'
-  schedule:
-    - cron: '40 3 * * *'   # every day at 3:40
-  pull_request:
-
-jobs:
-  test:
-    name: "Test"
-
-    strategy:
-      matrix:
-        platform: [
-          ubuntu-latest,
-          macos-latest,
-          windows-latest
-        ]
-
-    runs-on: ${{ matrix.platform }}
-    timeout-minutes: 15
-
-    steps:
-    - name: "Checkout Repository"
-      uses: actions/checkout@v1
-
-    - name: Install Rustup
-      run: |
-        curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --default-toolchain nightly
-        echo ::add-path::$HOME/.cargo/bin
-      if: runner.os == 'macOS'
-
-    - name: "Print Rust Version"
-      run: |
-        rustc -Vv
-        cargo -Vv
-
-    - name: "Install Rustup Components"
-      run: rustup component add rust-src llvm-tools-preview
-    - name: "Install cargo-xbuild"
-      run: cargo install cargo-xbuild --debug
-    - name: "Install bootimage"
-      run: cargo install bootimage --debug
-
-    - name: "Run cargo xbuild"
-      run: cargo xbuild
-    - name: "Create Bootimage"
-      run: cargo bootimage
-
-     # install QEMU
-    - name: Install QEMU (Linux)
-      run: sudo apt update && sudo apt install qemu-system-x86
-      if: runner.os == 'Linux'
-    - name: Install QEMU (macOS)
-      run: brew install qemu
-      if: runner.os == 'macOS'
-      env:
-        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
-      if: runner.os == 'Windows'
-      shell: pwsh
-    - name: "Print QEMU Version"
-      run: qemu-system-x86_64 --version
-
-    - name: "Run cargo xtest"
-      run: cargo xtest
-
-  check_formatting:
-    name: "Check Formatting"
-    runs-on: ubuntu-latest
-    timeout-minutes: 2
-    steps:
-    - uses: actions/checkout@v1
-    - name: "Use the latest Rust nightly with rustfmt"
-      uses: actions-rs/toolchain@v1
-      with:
-          toolchain: nightly
-          profile: minimal
-          components: rustfmt
-          override: true
-    - run: cargo fmt -- --check

.github/workflows/code.yml

@@ -0,0 +1,130 @@
+name: Code
+
+on:
+  push:
+    branches:
+      - '*'
+      - '!staging.tmp'
+    tags:
+      - '*'
+  schedule:
+    - cron: '40 3 * * *'   # every day at 3:40
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  check:
+    name: Check
+    strategy:
+      fail-fast: false
+      matrix:
+        platform: [
+          ubuntu-latest,
+          macos-latest,
+          windows-latest
+        ]
+    runs-on: ${{ matrix.platform }}
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: Install Rust Toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+      - name: Install `rust-src` Rustup Component
+        run: rustup component add rust-src
+      - name: Run `cargo check`
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+
+  test:
+    name: Test
+    strategy:
+      fail-fast: false
+      matrix:
+        platform: [
+          ubuntu-latest,
+          macos-latest,
+          windows-latest
+        ]
+    runs-on: ${{ matrix.platform }}
+    steps:
+      - name: Install Rust Toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+      - name: Install bootimage
+        run: cargo install bootimage --debug
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: Install Rustup Components
+        run: rustup component add rust-src llvm-tools-preview
+      - name: Run `cargo bootimage`
+        uses: actions-rs/cargo@v1
+        with:
+          command: bootimage
+
+      # install QEMU
+      - name: Install QEMU (Linux)
+        run: sudo apt update && sudo apt install qemu-system-x86
+        if: runner.os == 'Linux'
+      - name: Install QEMU (macOS)
+        run: brew install qemu
+        if: runner.os == 'macOS'
+        env:
+          HOMEBREW_NO_AUTO_UPDATE: 1
+          HOMEBREW_NO_BOTTLE_SOURCE_FALLBACK: 1
+          HOMEBREW_NO_INSTALL_CLEANUP: 1
+      - name: Install QEMU (Windows)
+        run: |
+          choco install qemu --version 2021.5.5
+          echo "$Env:Programfiles\qemu" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+        if: runner.os == 'Windows'
+        shell: pwsh
+      - name: "Print QEMU Version"
+        run: qemu-system-x86_64 --version
+
+      - name: Run `cargo test`
+        uses: actions-rs/cargo@v1
+        with:
+          command: test
+
+  check_formatting:
+    name: Check Formatting
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: Install Rust Toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          components: rustfmt
+          override: true
+      - name: Run `cargo fmt`
+        uses: actions-rs/cargo@v1
+        with:
+          command: fmt
+          args: --all -- --check
+
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v2
+      - name: Install Rust Toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          components: clippy, rust-src
+          override: true
+      - name: Run `cargo clippy`
+        uses: actions-rs/cargo@v1
+        with:
+          command: clippy

Cargo.lock

@@ -1,10 +1,12 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 4
+
 [[package]]
 name = "bit_field"
-version = "0.9.0"
+version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed8765909f9009617974ab6b7d332625b320b33c326b1e9321382ef1999b5d56"
+checksum = "dcb6dd1c2376d2e096796e234a70e17e94cc2d5d54ff8ce42b28cef1d0d359a4"
 
 [[package]]
 name = "bitflags"
@@ -19,24 +21,18 @@ dependencies = [
  "bootloader",
  "lazy_static",
  "pc-keyboard",
- "pic8259_simple",
+ "pic8259",
  "spin",
  "uart_16550",
- "volatile",
+ "volatile 0.2.7",
  "x86_64",
 ]
 
 [[package]]
 name = "bootloader"
-version = "0.8.8"
+version = "0.9.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c3ed4f735c4e455ba86a3d2939b1c0729414153642106c9d035693355630a42c"
-
-[[package]]
-name = "cpuio"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "22b8e308ccfc5acf3b82f79c0eac444cf6114cb2ac67a230ca6c177210068daa"
+checksum = "974e79cf1b0b737839f01330fb5393095daf1124d52693696494e32523ae9ef5"
 
 [[package]]
 name = "lazy_static"
@@ -49,17 +45,17 @@ dependencies = [
 
 [[package]]
 name = "pc-keyboard"
-version = "0.5.0"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c48392db76c4e9a69e0b3be356c5f97ebb7b14413c5e4fd0af4755dbf86e2fce"
+checksum = "ed089a1fbffe3337a1a345501c981f1eb1e47e69de5a40e852433e12953c3174"
 
 [[package]]
-name = "pic8259_simple"
-version = "0.1.1"
+name = "pic8259"
+version = "0.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dc64b2fd10828da8521b6cdabe0679385d7d2a3a6d4c336b819d1fa31ba35c72"
+checksum = "08cc920d83ee33c0f9b73aa441e75468bf2d10c959a3eb6260cf720b05ac91a1"
 dependencies = [
- "cpuio",
+ "x86_64",
 ]
 
 [[package]]
@@ -70,9 +66,9 @@ checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
 [[package]]
 name = "uart_16550"
-version = "0.2.4"
+version = "0.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d44b0f30cb82b0fbc15b78ade1064226529ad52028bc8cb8accb98ff6f3d7131"
+checksum = "503a6c0e6d82daa87985e662d120c0176b09587c92a68db22781b28ae95405dd"
 dependencies = [
  "bitflags",
  "x86_64",
@@ -80,16 +76,23 @@ dependencies = [
 
 [[package]]
 name = "volatile"
-version = "0.2.6"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6af0edf5b4faacc31fc51159244d78d65ec580f021afcef7bd53c04aeabc7f29"
+checksum = "f6b06ad3ed06fef1713569d547cdbdb439eafed76341820fb0e0344f29a41945"
+
+[[package]]
+name = "volatile"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e4c2dbd44eb8b53973357e6e207e370f0c1059990df850aca1eca8947cf464f0"
 
 [[package]]
 name = "x86_64"
-version = "0.9.6"
+version = "0.14.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4206b60c9f99766329b66962aa8ddc01df6c7edd02edc046b7a69d5df9fcdbcf"
+checksum = "fb611915c917c6296d11e23f71ff1ecfe49c5766daba92cd3df52df6b58285b6"
 dependencies = [
  "bit_field",
  "bitflags",
+ "volatile 0.4.4",
 ]

Cargo.toml

@@ -2,7 +2,7 @@
 name = "blog_os"
 version = "0.1.0"
 authors = ["Philipp Oppermann <dev@phil-opp.com>"]
-edition = "2018"
+edition = "2024"
 
 [[test]]
 name = "should_panic"
@@ -13,13 +13,13 @@ name = "stack_overflow"
 harness = false
 
 [dependencies]
-bootloader = { version = "0.8.0", features = ["map_physical_memory"]}
+bootloader = { version = "0.9", features = ["map_physical_memory"] }
 volatile = "0.2.6"
 spin = "0.5.2"
-x86_64 = "0.9.6"
+x86_64 = "0.14.2"
 uart_16550 = "0.2.0"
-pic8259_simple = "0.1.1"
-pc-keyboard = "0.5.0"
+pic8259 = "0.10.1"
+pc-keyboard = "0.7.0"
 
 [dependencies.lazy_static]
 version = "1.0"
@@ -28,7 +28,11 @@ features = ["spin_no_std"]
 
 [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

README.md

@@ -1,6 +1,6 @@
 # Blog OS (Paging Implementation)
 
-[![Build Status](https://github.com/phil-opp/blog_os/workflows/Build%20Code/badge.svg?branch=post-09)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Build+Code%22+branch%3Apost-09)
+[![Build Status](https://github.com/phil-opp/blog_os/workflows/Code/badge.svg?branch=post-09)](https://github.com/phil-opp/blog_os/actions?query=workflow%3A%22Code%22+branch%3Apost-09)
 
 This repository contains the source code for the [Paging Implementation][post] post of the [Writing an OS in Rust](https://os.phil-opp.com) series.
 
@@ -10,19 +10,23 @@ This repository contains the source code for the [Paging Implementation][post] p
 
 ## Building
 
-You need a nightly Rust compiler. First you need to install the `cargo-xbuild` and `bootimage` tools:
+This project requires a nightly version of Rust because it uses some unstable features. At least nightly _2020-07-15_ is required for building. You might need to run `rustup update nightly --force` to update to the latest nightly even if some components such as `rustfmt` are missing it.
+
+You can build the project by running:
 
 ```
-cargo install cargo-xbuild bootimage
+cargo build
 ```
 
-Then you can build the project by running:
+To create a bootable disk image from the compiled kernel, you need to install the [`bootimage`] tool:
+
+[`bootimage`]: https://github.com/rust-osdev/bootimage
 
 ```
-cargo xbuild
+cargo install bootimage
 ```
 
-To create a bootable disk image, run:
+After installing, you can create the bootable disk image by running:
 
 ```
 cargo bootimage
@@ -39,10 +43,10 @@ You can run the disk image in [QEMU] through:
 [QEMU]: https://www.qemu.org/
 
 ```
-cargo xrun
+cargo run
 ```
 
-Of course [QEMU] needs to be installed for this.
+[QEMU] and the [`bootimage`] tool need to be installed for this.
 
 You can also write the image to an USB stick for booting it on a real machine. On Linux, the command for this is:
 

src/gdt.rs

@@ -1,7 +1,7 @@
 use lazy_static::lazy_static;
+use x86_64::VirtAddr;
 use x86_64::structures::gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector};
 use x86_64::structures::tss::TaskStateSegment;
-use x86_64::VirtAddr;
 
 pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
 
@@ -9,10 +9,10 @@ lazy_static! {
     static ref TSS: TaskStateSegment = {
         let mut tss = TaskStateSegment::new();
         tss.interrupt_stack_table[DOUBLE_FAULT_IST_INDEX as usize] = {
-            const STACK_SIZE: usize = 4096;
+            const STACK_SIZE: usize = 4096 * 5;
             static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
 
-            let stack_start = VirtAddr::from_ptr(unsafe { &STACK });
+            let stack_start = VirtAddr::from_ptr(&raw const STACK);
             let stack_end = stack_start + STACK_SIZE;
             stack_end
         };
@@ -41,12 +41,12 @@ struct Selectors {
 }
 
 pub fn init() {
-    use x86_64::instructions::segmentation::set_cs;
+    use x86_64::instructions::segmentation::{CS, Segment};
     use x86_64::instructions::tables::load_tss;
 
     GDT.0.load();
     unsafe {
-        set_cs(GDT.1.code_selector);
+        CS::set_reg(GDT.1.code_selector);
         load_tss(GDT.1.tss_selector);
     }
 }

src/interrupts.rs

@@ -1,6 +1,6 @@
 use crate::{gdt, hlt_loop, print, println};
 use lazy_static::lazy_static;
-use pic8259_simple::ChainedPics;
+use pic8259::ChainedPics;
 use spin;
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame, PageFaultErrorCode};
 
@@ -47,12 +47,12 @@ pub fn init_idt() {
     IDT.load();
 }
 
-extern "x86-interrupt" fn breakpoint_handler(stack_frame: &mut InterruptStackFrame) {
+extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
     println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
 }
 
 extern "x86-interrupt" fn page_fault_handler(
-    stack_frame: &mut InterruptStackFrame,
+    stack_frame: InterruptStackFrame,
     error_code: PageFaultErrorCode,
 ) {
     use x86_64::registers::control::Cr2;
@@ -65,13 +65,13 @@ extern "x86-interrupt" fn page_fault_handler(
 }
 
 extern "x86-interrupt" fn double_fault_handler(
-    stack_frame: &mut InterruptStackFrame,
+    stack_frame: InterruptStackFrame,
     _error_code: u64,
 ) -> ! {
     panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
 }
 
-extern "x86-interrupt" fn timer_interrupt_handler(_stack_frame: &mut InterruptStackFrame) {
+extern "x86-interrupt" fn timer_interrupt_handler(_stack_frame: InterruptStackFrame) {
     print!(".");
     unsafe {
         PICS.lock()
@@ -79,15 +79,18 @@ extern "x86-interrupt" fn timer_interrupt_handler(_stack_frame: &mut InterruptSt
     }
 }
 
-extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: &mut InterruptStackFrame) {
-    use pc_keyboard::{layouts, DecodedKey, HandleControl, Keyboard, ScancodeSet1};
+extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: InterruptStackFrame) {
+    use pc_keyboard::{DecodedKey, HandleControl, Keyboard, ScancodeSet1, layouts};
     use spin::Mutex;
     use x86_64::instructions::port::Port;
 
     lazy_static! {
-        static ref KEYBOARD: Mutex<Keyboard<layouts::Us104Key, ScancodeSet1>> = Mutex::new(
-            Keyboard::new(layouts::Us104Key, ScancodeSet1, HandleControl::Ignore)
-        );
+        static ref KEYBOARD: Mutex<Keyboard<layouts::Us104Key, ScancodeSet1>> =
+            Mutex::new(Keyboard::new(
+                ScancodeSet1::new(),
+                layouts::Us104Key,
+                HandleControl::Ignore
+            ));
     }
 
     let mut keyboard = KEYBOARD.lock();
@@ -109,13 +112,8 @@ extern "x86-interrupt" fn keyboard_interrupt_handler(_stack_frame: &mut Interrup
     }
 }
 
-#[cfg(test)]
-use crate::{serial_print, serial_println};
-
 #[test_case]
 fn test_breakpoint_exception() {
-    serial_print!("test_breakpoint_exception...");
     // invoke a breakpoint exception
     x86_64::instructions::interrupts::int3();
-    serial_println!("[ok]");
 }

src/lib.rs

@@ -19,11 +19,25 @@ pub fn init() {
     unsafe { interrupts::PICS.lock().initialize() };
     x86_64::instructions::interrupts::enable();
 }
+pub trait Testable {
+    fn run(&self) -> ();
+}
 
-pub fn test_runner(tests: &[&dyn Fn()]) {
+impl<T> Testable for T
+where
+    T: Fn(),
+{
+    fn run(&self) {
+        serial_print!("{}...\t", core::any::type_name::<T>());
+        self();
+        serial_println!("[ok]");
+    }
+}
+
+pub fn test_runner(tests: &[&dyn Testable]) {
     serial_println!("Running {} tests", tests.len());
     for test in tests {
-        test();
+        test.run();
     }
     exit_qemu(QemuExitCode::Success);
 }
@@ -58,7 +72,7 @@ pub fn hlt_loop() -> ! {
 }
 
 #[cfg(test)]
-use bootloader::{entry_point, BootInfo};
+use bootloader::{BootInfo, entry_point};
 
 #[cfg(test)]
 entry_point!(test_kernel_main);

src/main.rs

@@ -5,14 +5,14 @@
 #![reexport_test_harness_main = "test_main"]
 
 use blog_os::println;
-use bootloader::{entry_point, BootInfo};
+use bootloader::{BootInfo, entry_point};
 use core::panic::PanicInfo;
 
 entry_point!(kernel_main);
 
 fn kernel_main(boot_info: &'static BootInfo) -> ! {
     use blog_os::memory::{self, BootInfoFrameAllocator};
-    use x86_64::{structures::paging::Page, VirtAddr};
+    use x86_64::{VirtAddr, structures::paging::Page};
 
     println!("Hello World{}", "!");
     blog_os::init();
@@ -49,3 +49,8 @@ fn panic(info: &PanicInfo) -> ! {
 fn panic(info: &PanicInfo) -> ! {
     blog_os::test_panic_handler(info)
 }
+
+#[test_case]
+fn trivial_assertion() {
+    assert_eq!(1, 1);
+}

src/memory.rs

@@ -1,10 +1,9 @@
 use bootloader::bootinfo::{MemoryMap, MemoryRegionType};
 use x86_64::{
+    PhysAddr, VirtAddr,
     structures::paging::{
         FrameAllocator, Mapper, OffsetPageTable, Page, PageTable, PhysFrame, Size4KiB,
-        UnusedPhysFrame,
     },
-    PhysAddr, VirtAddr,
 };
 
 /// Initialize a new OffsetPageTable.
@@ -14,8 +13,10 @@ use x86_64::{
 /// `physical_memory_offset`. Also, this function must be only called once
 /// to avoid aliasing `&mut` references (which is undefined behavior).
 pub unsafe fn init(physical_memory_offset: VirtAddr) -> OffsetPageTable<'static> {
-    let level_4_table = active_level_4_table(physical_memory_offset);
-    OffsetPageTable::new(level_4_table, physical_memory_offset)
+    unsafe {
+        let level_4_table = active_level_4_table(physical_memory_offset);
+        OffsetPageTable::new(level_4_table, physical_memory_offset)
+    }
 }
 
 /// Returns a mutable reference to the active level 4 table.
@@ -33,7 +34,7 @@ unsafe fn active_level_4_table(physical_memory_offset: VirtAddr) -> &'static mut
     let virt = physical_memory_offset + phys.as_u64();
     let page_table_ptr: *mut PageTable = virt.as_mut_ptr();
 
-    &mut *page_table_ptr // unsafe
+    unsafe { &mut *page_table_ptr }
 }
 
 /// Creates an example mapping for the given page to frame `0xb8000`.
@@ -45,11 +46,12 @@ pub fn create_example_mapping(
     use x86_64::structures::paging::PageTableFlags as Flags;
 
     let frame = PhysFrame::containing_address(PhysAddr::new(0xb8000));
-    // FIXME: ONLY FOR TEMPORARY TESTING
-    let unused_frame = unsafe { UnusedPhysFrame::new(frame) };
     let flags = Flags::PRESENT | Flags::WRITABLE;
 
-    let map_to_result = mapper.map_to(page, unused_frame, flags, frame_allocator);
+    let map_to_result = unsafe {
+        // FIXME: this is not safe, we do it only for testing
+        mapper.map_to(page, frame, flags, frame_allocator)
+    };
     map_to_result.expect("map_to failed").flush();
 }
 
@@ -57,7 +59,7 @@ pub fn create_example_mapping(
 pub struct EmptyFrameAllocator;
 
 unsafe impl FrameAllocator<Size4KiB> for EmptyFrameAllocator {
-    fn allocate_frame(&mut self) -> Option<UnusedPhysFrame> {
+    fn allocate_frame(&mut self) -> Option<PhysFrame> {
         None
     }
 }
@@ -82,7 +84,7 @@ impl BootInfoFrameAllocator {
     }
 
     /// Returns an iterator over the usable frames specified in the memory map.
-    fn usable_frames(&self) -> impl Iterator<Item = UnusedPhysFrame> {
+    fn usable_frames(&self) -> impl Iterator<Item = PhysFrame> {
         // get usable regions from memory map
         let regions = self.memory_map.iter();
         let usable_regions = regions.filter(|r| r.region_type == MemoryRegionType::Usable);
@@ -91,14 +93,12 @@ impl BootInfoFrameAllocator {
         // transform to an iterator of frame start addresses
         let frame_addresses = addr_ranges.flat_map(|r| r.step_by(4096));
         // create `PhysFrame` types from the start addresses
-        let frames = frame_addresses.map(|addr| PhysFrame::containing_address(PhysAddr::new(addr)));
-        // we know that the frames are really unused
-        frames.map(|f| unsafe { UnusedPhysFrame::new(f) })
+        frame_addresses.map(|addr| PhysFrame::containing_address(PhysAddr::new(addr)))
     }
 }
 
 unsafe impl FrameAllocator<Size4KiB> for BootInfoFrameAllocator {
-    fn allocate_frame(&mut self) -> Option<UnusedPhysFrame> {
+    fn allocate_frame(&mut self) -> Option<PhysFrame> {
         let frame = self.usable_frames().nth(self.next);
         self.next += 1;
         frame

src/vga_buffer.rs

@@ -3,9 +3,6 @@ use lazy_static::lazy_static;
 use spin::Mutex;
 use volatile::Volatile;
 
-#[cfg(test)]
-use crate::{serial_print, serial_println};
-
 lazy_static! {
     /// A global `Writer` instance that can be used for printing to the VGA text buffer.
     ///
@@ -180,18 +177,14 @@ pub fn _print(args: fmt::Arguments) {
 
 #[test_case]
 fn test_println_simple() {
-    serial_print!("test_println... ");
     println!("test_println_simple output");
-    serial_println!("[ok]");
 }
 
 #[test_case]
 fn test_println_many() {
-    serial_print!("test_println_many... ");
     for _ in 0..200 {
         println!("test_println_many output");
     }
-    serial_println!("[ok]");
 }
 
 #[test_case]
@@ -199,8 +192,6 @@ fn test_println_output() {
     use core::fmt::Write;
     use x86_64::instructions::interrupts;
 
-    serial_print!("test_println_output... ");
-
     let s = "Some test string that fits on a single line";
     interrupts::without_interrupts(|| {
         let mut writer = WRITER.lock();
@@ -210,6 +201,4 @@ fn test_println_output() {
             assert_eq!(char::from(screen_char.ascii_character), c);
         }
     });
-
-    serial_println!("[ok]");
 }

tests/basic_boot.rs

@@ -4,10 +4,10 @@
 #![test_runner(blog_os::test_runner)]
 #![reexport_test_harness_main = "test_main"]
 
-use blog_os::{println, serial_print, serial_println};
+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();
 
@@ -21,7 +21,5 @@ fn panic(info: &PanicInfo) -> ! {
 
 #[test_case]
 fn test_println() {
-    serial_print!("test_println... ");
     println!("test_println output");
-    serial_println!("[ok]");
 }

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]");
@@ -13,7 +13,7 @@ pub extern "C" fn _start() -> ! {
 }
 
 fn should_fail() {
-    serial_print!("should_fail... ");
+    serial_print!("should_panic::should_fail...\t");
     assert_eq!(0, 1);
 }
 

tests/stack_overflow.rs

@@ -2,14 +2,14 @@
 #![no_main]
 #![feature(abi_x86_interrupt)]
 
-use blog_os::{exit_qemu, serial_print, serial_println, QemuExitCode};
+use blog_os::{QemuExitCode, exit_qemu, serial_print, serial_println};
 use core::panic::PanicInfo;
 use lazy_static::lazy_static;
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
 
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
-    serial_print!("stack_overflow... ");
+    serial_print!("stack_overflow::stack_overflow...\t");
 
     blog_os::gdt::init();
     init_test_idt();
@@ -23,6 +23,7 @@ pub extern "C" fn _start() -> ! {
 #[allow(unconditional_recursion)]
 fn stack_overflow() {
     stack_overflow(); // for each recursion, the return address is pushed
+    volatile::Volatile::new(0).read(); // prevent tail recursion optimizations
 }
 
 lazy_static! {
@@ -43,7 +44,7 @@ pub fn init_test_idt() {
 }
 
 extern "x86-interrupt" fn test_double_fault_handler(
-    _stack_frame: &mut InterruptStackFrame,
+    _stack_frame: InterruptStackFrame,
     _error_code: u64,
 ) -> ! {
     serial_println!("[ok]");

x86_64-blog_os.json

@@ -1,6 +1,6 @@
 {
     "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",
@@ -11,5 +11,6 @@
     "linker": "rust-lld",
     "panic-strategy": "abort",
     "disable-redzone": true,
-    "features": "-mmx,-sse,+soft-float"
+    "features": "-mmx,-sse,+soft-float",
+    "rustc-abi": "x86-softfloat"
   }