Fix interrupts causing exception 0xd

1 files changed, 9 insertions, 0 deletions

diff --git a/src/gdt.cc b/src/gdt.cc
index 289462b..9c86888 100644
--- a/src/gdt.cc
+++ b/src/gdt.cc
@@ -1,12 +1,21 @@
 #include "gdt.h"
+#include <stdlib.h>
 
 using seg = GDT::SegmentDescriptor;
 
 GDT::GDT()
     : segments{seg::make<0>(0, {.present = false}),                                    // null segment
+               seg::make<0>(0, {.present = false}),                                    // unused segment ???
                seg::make<0xffffffff>(0, {.r_w = true, .exe = true, .segment = true}),  // code segment
                seg::make<0xffffffff>(0, {.r_w = true, .segment = true})}               // data segment
 {
   Pointer gdtr{.limit = sizeof(segments) - 1, .base = reinterpret_cast<uint32_t>(segments)};
   asm volatile("lgdt %0" : : "p"(gdtr));
+
+  printk("GDT installed at ", uhex{gdtr.base}, '\n');
+}
+
+uint16_t GDT::codeDescriptor() const {
+  return static_cast<uint16_t>(reinterpret_cast<const uint32_t>(&segments[2]) -
+                               reinterpret_cast<const uint32_t>(&segments));
 }