From 090e0785ff7dec4eaee9a99ec3ad6e44638dc586 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Sun, 30 Oct 2016 17:51:26 +0100
Subject: [PATCH] Use references for the ExceptionStackFrame argument
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We require/assume that these pointers are correct. Using references is cleaner than blindly dereferencing raw pointers.

Important: The Rust book guarantees that: “At runtime, a raw pointer * and a reference pointing to the same piece of data have an identical representation.”
(cherry picked from commit 15feb9a1205f5a62ce9a42bc91009ac0bb7ed0d0)
---
 src/interrupts/mod.rs | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/interrupts/mod.rs b/src/interrupts/mod.rs
index 2a0223ea..af5e620c 100644
--- a/src/interrupts/mod.rs
+++ b/src/interrupts/mod.rs
@@ -18,7 +18,7 @@ macro_rules! handler {
                       sub rsp, 8 // align the stack pointer
                       call $0"
                       :: "i"($name as extern "C" fn(
-                          *const ExceptionStackFrame) -> !)
+                          &ExceptionStackFrame) -> !)
                       : "rdi" : "intel");
                 ::core::intrinsics::unreachable();
             }
@@ -37,7 +37,7 @@ macro_rules! handler_with_error_code {
                       sub rsp, 8 // align the stack pointer
                       call $0"
                       :: "i"($name as extern "C" fn(
-                          *const ExceptionStackFrame, u64) -> !)
+                          &ExceptionStackFrame, u64) -> !)
                       : "rdi","rsi" : "intel");
                 ::core::intrinsics::unreachable();
             }
@@ -72,14 +72,12 @@ struct ExceptionStackFrame {
     stack_segment: u64,
 }
 
-extern "C" fn divide_by_zero_handler(stack_frame: *const ExceptionStackFrame) -> ! {
-    let stack_frame = unsafe { &*stack_frame };
+extern "C" fn divide_by_zero_handler(stack_frame: &ExceptionStackFrame) -> ! {
     println!("\nEXCEPTION: DIVIDE BY ZERO\n{:#?}", stack_frame);
     loop {}
 }
 
-extern "C" fn invalid_opcode_handler(stack_frame: *const ExceptionStackFrame) -> ! {
-    let stack_frame = unsafe { &*stack_frame };
+extern "C" fn invalid_opcode_handler(stack_frame: &ExceptionStackFrame) -> ! {
     println!("\nEXCEPTION: INVALID OPCODE at {:#x}\n{:#?}",
              stack_frame.instruction_pointer,
              stack_frame);
@@ -96,8 +94,7 @@ bitflags! {
     }
 }
 
-extern "C" fn page_fault_handler(stack_frame: *const ExceptionStackFrame, error_code: u64) -> ! {
-    let stack_frame = unsafe { &*stack_frame };
+extern "C" fn page_fault_handler(stack_frame: &ExceptionStackFrame, error_code: u64) -> ! {
     use x86::controlregs;
     println!("\nEXCEPTION: PAGE FAULT while accessing {:#x}\nerror code: \
                                   {:?}\n{:#?}",