Set UCSEG and UDSEG in gdt.

e470eb3a · Silas Boyd-Wickizer · c53c558b · e470eb3a
--- a/trap.c
+++ b/trap.c
@@ -5,13 +5,17 @@

 struct segdesc  __attribute__((aligned(16))) bootgdt[NSEGS] = {
  // null
-  SEGDESC(0, 0, 0),
+  [0]=SEGDESC(0, 0, 0),
  // 32-bit kernel code
-  SEGDESC(0, 0xfffff, SEG_R|SEG_CODE|SEG_S|SEG_DPL(0)|SEG_P|SEG_D|SEG_G),
+  [1]=SEGDESC(0, 0xfffff, SEG_R|SEG_CODE|SEG_S|SEG_DPL(0)|SEG_P|SEG_D|SEG_G),
  // 64-bit kernel code
-  SEGDESC(0, 0, SEG_R|SEG_CODE|SEG_S|SEG_DPL(0)|SEG_P|SEG_L|SEG_G),
+  [2]=SEGDESC(0, 0, SEG_R|SEG_CODE|SEG_S|SEG_DPL(0)|SEG_P|SEG_L|SEG_G),
  // kernel data
-  SEGDESC(0, 0xfffff, SEG_W|SEG_S|SEG_DPL(0)|SEG_P|SEG_D|SEG_G)
+  [3]=SEGDESC(0, 0xfffff, SEG_W|SEG_S|SEG_DPL(0)|SEG_P|SEG_D|SEG_G),
+  // 64-bit user code
+  [6]=SEGDESC(0, 0, SEG_R|SEG_CODE|SEG_S|SEG_DPL(3)|SEG_P|SEG_L|SEG_G),  
+  // 64-bit user data
+  [7]=SEGDESC(0, 0xfffff, SEG_W|SEG_S|SEG_DPL(3)|SEG_P|SEG_D|SEG_G)
 };

 struct intdesc idt[256] __attribute__((aligned(16)));