From ff25a7d86c4ae051729d774859e59274432bddc3 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Fri, 25 Jan 2019 13:59:09 +0100
Subject: [PATCH] Reload code and TSS selector registers

---
 src/gdt.rs | 32 +++++++++++++++++++++++++-------
 1 file changed, 25 insertions(+), 7 deletions(-)

diff --git a/src/gdt.rs b/src/gdt.rs
index eae34bf4..de61a7d8 100644
--- a/src/gdt.rs
+++ b/src/gdt.rs
@@ -1,5 +1,5 @@
 use lazy_static::lazy_static;
-use x86_64::structures::gdt::{Descriptor, GlobalDescriptorTable};
+use x86_64::structures::gdt::{Descriptor, GlobalDescriptorTable, SegmentSelector};
 use x86_64::structures::tss::TaskStateSegment;
 use x86_64::VirtAddr;
 
@@ -21,14 +21,32 @@ lazy_static! {
 }
 
 lazy_static! {
-    static ref GDT: GlobalDescriptorTable = {
+    static ref GDT: (GlobalDescriptorTable, Selectors) = {
         let mut gdt = GlobalDescriptorTable::new();
-        gdt.add_entry(Descriptor::kernel_code_segment());
-        gdt.add_entry(Descriptor::tss_segment(&TSS));
-        gdt
+        let code_selector = gdt.add_entry(Descriptor::kernel_code_segment());
+        let tss_selector = gdt.add_entry(Descriptor::tss_segment(&TSS));
+        (
+            gdt,
+            Selectors {
+                code_selector,
+                tss_selector,
+            },
+        )
     };
 }
 
-pub fn init() {
-    GDT.load();
+struct Selectors {
+    code_selector: SegmentSelector,
+    tss_selector: SegmentSelector,
+}
+
+pub fn init() {
+    use x86_64::instructions::segmentation::set_cs;
+    use x86_64::instructions::tables::load_tss;
+
+    GDT.0.load();
+    unsafe {
+        set_cs(GDT.1.code_selector);
+        load_tss(GDT.1.tss_selector);
+    }
 }