Added more interrupt handlers to aid debugging

Several common CPU exceptions had no handler previously, leading
to a double fault if they were triggered. This makes debugging
difficult, as we don't know what exactly went wrong. This adds
basic panicking handlers for them, so that at least we know the
error more specifically.

Signed-off-by: SlyMarbo <[email protected]>

Author: SlyMarbo

kernel/src/interrupts.rs

@@ -48,12 +48,17 @@ lazy_static! {
     static ref IDT: InterruptDescriptorTable = {
         let mut idt = InterruptDescriptorTable::new();
         idt.breakpoint.set_handler_fn(breakpoint_handler);
-        idt.page_fault.set_handler_fn(page_fault_handler);
+        idt.invalid_opcode.set_handler_fn(invalid_opcode_handler);
         unsafe {
             idt.double_fault
                 .set_handler_fn(double_fault_handler)
                 .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX);
         }
+        idt.segment_not_present
+            .set_handler_fn(segment_not_present_handler);
+        idt.general_protection_fault
+            .set_handler_fn(general_protection_fault_handler);
+        idt.page_fault.set_handler_fn(page_fault_handler);
 
         idt[PIC_1_OFFSET + 0].set_handler_fn(irq_handler_0);
         idt[PIC_1_OFFSET + 1].set_handler_fn(irq_handler_1);
@@ -76,12 +81,47 @@ lazy_static! {
     };
 }
 
-// Interrupt handlers.
+// CPU exception handlers.
 
 extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
     println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
 }
 
+extern "x86-interrupt" fn invalid_opcode_handler(stack_frame: InterruptStackFrame) {
+    panic!("EXCEPTION: INVALID OPCODE\n{:#?}", stack_frame);
+}
+
+extern "x86-interrupt" fn double_fault_handler(
+    stack_frame: InterruptStackFrame,
+    _error_code: u64,
+) -> ! {
+    panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
+}
+
+extern "x86-interrupt" fn segment_not_present_handler(
+    stack_frame: InterruptStackFrame,
+    error_code: u64,
+) {
+    panic!(
+        "EXCEPTION: SEGMENT NOT PRESENT: index {}\n{:#?}",
+        error_code, stack_frame
+    );
+}
+
+extern "x86-interrupt" fn general_protection_fault_handler(
+    stack_frame: InterruptStackFrame,
+    error_code: u64,
+) {
+    if error_code != 0 {
+        panic!(
+            "EXCEPTION: GENERAL PROTECTION FAULT: segment index {}\n{:#?}",
+            error_code, stack_frame
+        );
+    } else {
+        panic!("EXCEPTION: GENERAL PROTECTION FAULT:\n{:#?}", stack_frame);
+    }
+}
+
 extern "x86-interrupt" fn page_fault_handler(
     stack_frame: InterruptStackFrame,
     error_code: PageFaultErrorCode,
@@ -93,12 +133,7 @@ extern "x86-interrupt" fn page_fault_handler(
     halt_loop();
 }
 
-extern "x86-interrupt" fn double_fault_handler(
-    stack_frame: InterruptStackFrame,
-    _error_code: u64,
-) -> ! {
-    panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
-}
+// IRQ handlers.
 
 fn timer_interrupt_handler(_stack_frame: InterruptStackFrame, _irq: u8) {
     time::tick();