use long mode, x86_64-unknown-none works now

src/lib.rs

@@ -6,15 +6,22 @@ use core::panic::PanicInfo;
 #[unsafe(no_mangle)]
 pub extern "C" fn _start() -> ! {
     // 'k'
-    loop{unsafe {core::arch::asm!(
-        "out dx, al", in("al") 0x6Bu8
-    )}}
+    print("kernel\n");
+    loop {}
+}
+
+fn print(s: &str) {
+    let mut bytes = s.bytes();
+    while let Some(b) = bytes.next() {
+        unsafe {core::arch::asm!(
+            "out dx, al"
+            , in("al") b
+        )};
+    };
 }
 
 #[panic_handler]
 fn panic(_: &PanicInfo) -> ! {
-    // 'p'
-    loop{unsafe {core::arch::asm!(
-        "out dx, al", in("al") 0x70u8
-    )}}
+    print("panicked");
+    loop {}
 }