Add expect fault handling

7 files changed, 80 insertions, 38 deletions

diff --git a/kernel/Cargo.toml b/kernel/Cargo.toml
index a2ce08c..1baefdb 100644
--- a/kernel/Cargo.toml
+++ b/kernel/Cargo.toml
@@ -5,8 +5,13 @@ authors = ["Dennis Kobert <dennis@kobert.dev>",
            "Jan Zwerschke"]
 edition = "2018"
 
-# [lib]
-# crate-type = ["staticlib"]
+[[test]]
+name = "int3"
+harness = false
+
+[[test]]
+name = "stack_overflow"
+harness = false
 
 [package.metadata.cargo-xbuild]
 sysroot_path = "target/sysroot"
diff --git a/kernel/src/interrupts/exceptions.rs b/kernel/src/interrupts/exceptions.rs
index 1e7680a..f6d5176 100644
--- a/kernel/src/interrupts/exceptions.rs
+++ b/kernel/src/interrupts/exceptions.rs
@@ -1,3 +1,5 @@
+use super::Interrupts;
+use crate::io::qemu;
 use x86_64::structures::idt::{InterruptStackFrame, PageFaultErrorCode};
 
 macro_rules! exception_default {
@@ -11,11 +13,26 @@ macro_rules! exception_default {
     };
 }
 
+static mut expected_fault: Interrupts = Interrupts::NONE;
+
+pub unsafe fn expect_fault(int: Interrupts) {
+    if expected_fault == Interrupts::NONE {
+        expected_fault = int;
+    }
+}
+
+fn get_expected_fault() -> Interrupts {
+    unsafe { expected_fault }
+}
+
 pub extern "x86-interrupt" fn breakpoint_handler(stack_frame: &mut InterruptStackFrame) {
-    panic!(
-        "BREAKPOINT exception thrown\n\n{}",
-        exception_default!(stack_frame)
-    );
+    match get_expected_fault() {
+        Interrupts::BREAKPOINT => qemu::exit_qemu(qemu::QemuExitCode::Success),
+        _ => panic!(
+            "BREAKPOINT exception thrown\n\n{}",
+            exception_default!(stack_frame)
+        ),
+    }
 }
 
 pub extern "x86-interrupt" fn page_fault_handler(
@@ -24,32 +41,41 @@ pub extern "x86-interrupt" fn page_fault_handler(
 ) {
     use x86_64::registers::control::Cr2;
 
-    panic!(
-        "PAGE FAULT while accessing address: 0x{:08x}\nerror code: {:?}(0x{:x})\n{}",
-        Cr2::read().as_u64(),
-        error_code,
-        error_code.bits(),
-        exception_default!(stack_frame)
-    );
+    match get_expected_fault() {
+        Interrupts::PAGE_FAULT => qemu::exit_qemu(qemu::QemuExitCode::Success),
+        _ => panic!(
+            "PAGE FAULT while accessing address: 0x{:08x}\nerror code: {:?}(0x{:x})\n{}",
+            Cr2::read().as_u64(),
+            error_code,
+            error_code.bits(),
+            exception_default!(stack_frame)
+        ),
+    }
 }
 
 pub extern "x86-interrupt" fn segment_not_present_handler(
     stack_frame: &mut InterruptStackFrame,
     error_code: u64,
 ) {
-    panic!(
-        "SEGMENT NOT PRESENT exception\nerror code: 0x{:x}\n{}",
-        error_code,
-        exception_default!(stack_frame)
-    );
+    match get_expected_fault() {
+        Interrupts::NOT_PRESENT => qemu::exit_qemu(qemu::QemuExitCode::Success),
+        _ => panic!(
+            "SEGMENT NOT PRESENT exception\nerror code: 0x{:x}\n{}",
+            error_code,
+            exception_default!(stack_frame)
+        ),
+    }
 }
 
 pub extern "x86-interrupt" fn double_fault_handler(
     stack_frame: &mut InterruptStackFrame,
     _error_code: u64, // code is always zero
 ) {
-    panic!(
-        "DOUBLE FAULT\nthis is a fatal exception\n{}",
-        exception_default!(stack_frame)
-    );
+    match get_expected_fault() {
+        Interrupts::NOT_PRESENT => qemu::exit_qemu(qemu::QemuExitCode::Success),
+        _ => panic!(
+            "DOUBLE FAULT\nthis is a fatal exception\n{}",
+            exception_default!(stack_frame)
+        ),
+    }
 }
diff --git a/kernel/src/interrupts/table.rs b/kernel/src/interrupts/idt.rs
index 9541f22..9541f22 100644
--- a/kernel/src/interrupts/table.rs
+++ b/kernel/src/interrupts/idt.rs
diff --git a/kernel/src/interrupts/mod.rs b/kernel/src/interrupts/mod.rs
index 14de3f2..4ff3c4d 100644
--- a/kernel/src/interrupts/mod.rs
+++ b/kernel/src/interrupts/mod.rs
@@ -1,3 +1,13 @@
-mod exceptions;
+pub mod exceptions;
 pub mod gdt;
-pub mod table;
+pub mod idt;
+
+#[repr(usize)]
+#[derive(PartialEq, Clone, Copy)]
+pub enum Interrupts {
+    NONE,
+    PAGE_FAULT,
+    DOUBLE_FAULT,
+    NOT_PRESENT,
+    BREAKPOINT,
+}
diff --git a/kernel/src/lib.rs b/kernel/src/lib.rs
index 52d41ed..8ab660d 100644
--- a/kernel/src/lib.rs
+++ b/kernel/src/lib.rs
@@ -32,5 +32,5 @@ fn panic(info: &core::panic::PanicInfo) -> ! {
 
 pub fn init() {
     interrupts::gdt::init();
-    interrupts::table::init();
+    interrupts::idt::init();
 }
diff --git a/kernel/tests/int3.rs b/kernel/tests/int3.rs
index 771c17d..f4e2116 100644
--- a/kernel/tests/int3.rs
+++ b/kernel/tests/int3.rs
@@ -1,28 +1,26 @@
 #![no_main]
 #![feature(compiler_builtins_lib)]
-#![feature(custom_test_frameworks)]
 #![feature(abi_x86_interrupt)]
 #![feature(panic_info_message)]
-#![test_runner(kernel::testing::serial_test_runner)]
-#![reexport_test_harness_main = "test_main"]
 #![no_std]
 
 use kernel;
+use kernel::interrupts;
+use kernel::interrupts::exceptions;
 use kernel::io::qemu;
 
 #[no_mangle]
 extern "C" fn _start() -> ! {
     kernel::init();
-    test_main();
+    unsafe {
+        exceptions::expect_fault(interrupts::Interrupts::BREAKPOINT);
+    }
+    x86_64::instructions::interrupts::int3();
+    panic!("BREAKPOINT not caught");
 
     loop {}
 }
 
-#[test_case]
-fn breakpoint() {
-    x86_64::instructions::interrupts::int3();
-}
-
 #[cfg(test)]
 #[panic_handler]
 #[no_mangle]
diff --git a/kernel/tests/stack_overflow.rs b/kernel/tests/stack_overflow.rs
index 677a9e1..dc53537 100644
--- a/kernel/tests/stack_overflow.rs
+++ b/kernel/tests/stack_overflow.rs
@@ -1,25 +1,28 @@
 #![no_main]
 #![feature(compiler_builtins_lib)]
-#![feature(custom_test_frameworks)]
 #![feature(abi_x86_interrupt)]
 #![feature(panic_info_message)]
-#![test_runner(kernel::testing::serial_test_runner_panic)]
 #![no_std]
 
 use core::fmt::Write;
 use kernel;
+use kernel::interrupts;
+use kernel::interrupts::exceptions;
 use kernel::io::qemu;
 
 #[no_mangle]
 extern "C" fn _start() -> ! {
     kernel::init();
+    unsafe {
+        exceptions::expect_fault(interrupts::Interrupts::PAGE_FAULT);
+    }
     _loop(0);
-
+    panic!("PAGE_FAULT not caught");
     loop {}
 }
 
 fn _loop(i: u128) -> u128 {
-    if i > 1u128 << 83 {
+    if i > 1u128 << 120 {
         return i;
     }
     let n = i;