Allow for registering "signal" handlers for exceptions (#501)

* There are four categories of "signals" that correspond loosely to POSIX error-related signals: SIGSEGV, SIGBUS, SIGFPE, SIGILL. 

* Clean up exception handling code, including logging faults and killing tasks.

Author: kevinaboos

Cargo.lock

@@ -108,43 +108,43 @@ pub fn init(double_fault_stack_top_unusable: Option<memory::VirtualAddress>) {
 
 
 /// exception 0x00
-pub extern "x86-interrupt" fn divide_error_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn divide_error_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): DIVIDE ERROR\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x01
-pub extern "x86-interrupt" fn debug_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn debug_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): DEBUG EXCEPTION\n{:#X?}", stack_frame);
     // don't halt here, this isn't a fatal/permanent failure, just a brief pause.
 }
 
 /// exception 0x02
-pub extern "x86-interrupt" fn nmi_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn nmi_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): NON-MASKABLE INTERRUPT\n{:#X?}", stack_frame);
     loop { }
 }
 
 /// exception 0x03
-pub extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn breakpoint_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): BREAKPOINT\n{:#X?}", stack_frame);
     // don't halt here, this isn't a fatal/permanent failure, just a brief pause.
 }
 
 /// exception 0x04
-pub extern "x86-interrupt" fn overflow_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn overflow_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): OVERFLOW\n{:#X?}", stack_frame);
     loop { }
 }
 
 /// exception 0x05
-pub extern "x86-interrupt" fn bound_range_exceeded_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn bound_range_exceeded_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): BOUND RANGE EXCEEDED\n{:#X?}", stack_frame);
     loop { }
 }
 
 /// exception 0x06
-pub extern "x86-interrupt" fn invalid_opcode_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn invalid_opcode_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): INVALID OPCODE\n{:#X?}", stack_frame);
     loop {}
 }
@@ -153,44 +153,46 @@ pub extern "x86-interrupt" fn invalid_opcode_handler(stack_frame: InterruptStack
 /// 
 /// For more information about "spurious interrupts", 
 /// see [here](http://wiki.osdev.org/I_Cant_Get_Interrupts_Working#I_keep_getting_an_IRQ7_for_no_apparent_reason).
-pub extern "x86-interrupt" fn device_not_available_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn device_not_available_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): DEVICE NOT AVAILABLE\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x08
+/// 
+/// Note: this is `pub` so we can access it within `interrupts::init()`.
 pub extern "x86-interrupt" fn double_fault_handler(stack_frame: InterruptStackFrame, error_code: u64) -> ! {
     println_raw!("\nEXCEPTION (early): DOUBLE FAULT\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     println_raw!("\nNote: this may be caused by stack overflow. Is the size of the initial_bsp_stack is too small?");
     loop {}
 }
 
 /// exception 0x0A
-pub extern "x86-interrupt" fn invalid_tss_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn invalid_tss_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): INVALID TSS\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x0B
-pub extern "x86-interrupt" fn segment_not_present_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn segment_not_present_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): SEGMENT NOT PRESENT\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x0C
-pub extern "x86-interrupt" fn stack_segment_fault_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn stack_segment_fault_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): STACK SEGMENT FAULT\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x0D
-pub extern "x86-interrupt" fn general_protection_fault_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn general_protection_fault_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): GENERAL PROTECTION FAULT\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x0E
-pub extern "x86-interrupt" fn early_page_fault_handler(stack_frame: InterruptStackFrame, error_code: PageFaultErrorCode) {
+extern "x86-interrupt" fn early_page_fault_handler(stack_frame: InterruptStackFrame, error_code: PageFaultErrorCode) {
     let accessed_address = x86_64::registers::control::Cr2::read_raw();
     println_raw!("\nEXCEPTION (early): PAGE FAULT (early handler) while accessing {:#x}\n\
         error code: {:?}\n{:#X?}",
@@ -217,43 +219,43 @@ pub extern "x86-interrupt" fn early_page_fault_handler(stack_frame: InterruptSta
 }
 
 /// exception 0x10
-pub extern "x86-interrupt" fn x87_floating_point_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn x87_floating_point_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): x87 FLOATING POINT\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x11
-pub extern "x86-interrupt" fn alignment_check_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn alignment_check_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): ALIGNMENT CHECK\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x12
-pub extern "x86-interrupt" fn machine_check_handler(stack_frame: InterruptStackFrame) -> ! {
+extern "x86-interrupt" fn machine_check_handler(stack_frame: InterruptStackFrame) -> ! {
     println_raw!("\nEXCEPTION (early): MACHINE CHECK\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x13
-pub extern "x86-interrupt" fn simd_floating_point_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn simd_floating_point_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): SIMD FLOATING POINT\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x14
-pub extern "x86-interrupt" fn virtualization_handler(stack_frame: InterruptStackFrame) {
+extern "x86-interrupt" fn virtualization_handler(stack_frame: InterruptStackFrame) {
     println_raw!("\nEXCEPTION (early): VIRTUALIZATION\n{:#X?}", stack_frame);
     loop {}
 }
 
 /// exception 0x1D
-pub extern "x86-interrupt" fn vmm_communication_exception_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn vmm_communication_exception_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): VMM COMMUNICATION EXCEPTION\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }
 
 /// exception 0x1E
-pub extern "x86-interrupt" fn security_exception_handler(stack_frame: InterruptStackFrame, error_code: u64) {
+extern "x86-interrupt" fn security_exception_handler(stack_frame: InterruptStackFrame, error_code: u64) {
     println_raw!("\nEXCEPTION (early): SECURITY EXCEPTION\n{:#X?}\nError code: {:#b}", stack_frame, error_code);
     loop {}
 }

kernel/exceptions_early/src/lib.rs

@@ -7,14 +7,7 @@ build = "../../build.rs"
 
 [dependencies]
 x86_64 = { path = "../../libs/x86_64" } # currently using our local copy, forked from Phil Opp's crate
-
-[dependencies.log]
-version = "0.4.8"
-
-[dependencies.gimli]
-version = "0.19.0"
-default-features = false
-features = [ "read", "alloc" ]
+log = "0.4.8"
 
 [dependencies.vga_buffer]
 path = "../vga_buffer"
@@ -55,5 +48,8 @@ path = "../tss"
 [dependencies.debug_info]
 path = "../debug_info"
 
+[dependencies.signal_handler]
+path = "../signal_handler"
+
 [lib]
 crate-type = ["rlib"]