src/gdt.rs

@@ -1,47 +0,0 @@
-use x86_64::VirtAddr;
-use x86_64::structures::tss::TaskStateSegment;
-use lazy_static::lazy_static;
-use x86_64::structures::gdt::{GlobalDescriptorTable, Descriptor};
-use x86_64::structures::gdt::SegmentSelector;
-
-pub const DOUBLE_FAULT_IST_INDEX: u16 = 0;
-
-pub fn init() {
-    use x86_64::instructions::tables::load_tss;
-    use x86_64::instructions::segmentation::{CS, Segment};
-
-    GDT.0.load();
-    unsafe {
-        CS::set_reg(GDT.1.code_selector);
-        load_tss(GDT.1.tss_selector);
-    }
-}
-
-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 * 5;
-            static mut STACK: [u8; STACK_SIZE] = [0; STACK_SIZE];
-
-            let stack_start = VirtAddr::from_ptr(unsafe { &STACK });
-            let stack_end = stack_start + STACK_SIZE;
-            stack_end
-        };
-        tss
-    };
-}
-
-lazy_static! {
-    static ref GDT: (GlobalDescriptorTable, Selectors) = {
-        let mut gdt = GlobalDescriptorTable::new();
-        let code_selector = gdt.add_entry(Descriptor::kernel_code_segment());
-        let tss_selector = gdt.add_entry(Descriptor::tss_segment(&TSS));
-        (gdt, Selectors { code_selector, tss_selector })
-    };
-}
-
-struct Selectors {
-    code_selector: SegmentSelector,
-    tss_selector: SegmentSelector,
-}

src/interrupts.rs

@@ -1,17 +1,10 @@
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
 use crate::println;
 use lazy_static::lazy_static;
-use crate::gdt;
-
 lazy_static! {
     static ref IDT: InterruptDescriptorTable = {
         let mut idt = InterruptDescriptorTable::new();
         idt.breakpoint.set_handler_fn(breakpoint_handler);
-        unsafe {
-            idt.double_fault.set_handler_fn(double_fault_handler)
-                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX); // new
-        }
-
         idt
     };
 }
@@ -25,15 +18,3 @@ extern "x86-interrupt" fn breakpoint_handler(
 {
     println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
 }
-
-extern "x86-interrupt" fn double_fault_handler(
-    stack_frame: InterruptStackFrame, _error_code: u64) -> !
-{
-    panic!("EXCEPTION: DLB FAULT\n{:#?}", stack_frame);
-}
-
-#[test_case]
-fn test_breakpoint_exception() {
-    // invoke a breakpoint exception
-    x86_64::instructions::interrupts::int3();
-}

src/lib.rs

@@ -6,16 +6,13 @@
 #![reexport_test_harness_main = "test_main"]
 #![feature(abi_x86_interrupt)]
 
+pub fn init() {
+    interrupts::init_idt();
+}
 
 pub mod serial;
 pub mod vga_buffer;
 pub mod interrupts;
-pub mod gdt;
-
-pub fn init() {
-    gdt::init();
-    interrupts::init_idt();
-}
 
 use core::panic::PanicInfo;
 
@@ -53,7 +50,6 @@ pub fn test_panic_handler(info: &PanicInfo) -> ! {
 #[cfg(test)]
 #[no_mangle]
 pub extern "C" fn _start() -> ! {
-    init();
     test_main();
     loop {}
 }

src/main.rs

@@ -13,11 +13,7 @@ pub extern "C" fn _start() -> ! {
 
     donald::init();
 
-    fn stack_overflow() {
+    x86_64::instructions::interrupts::int3();
-        stack_overflow();
-    }
-
-    stack_overflow();
 
     #[cfg(test)]
     test_main();