diff --git a/arch/x86_64/src/start.rs b/arch/x86_64/src/start.rs
index 7748a00..c941a88 100644
--- a/arch/x86_64/src/start.rs
+++ b/arch/x86_64/src/start.rs
@@ -178,8 +178,7 @@ pub unsafe extern fn kstart_ap(cpu_id: usize, page_table: usize, stack_start: us
 
 pub unsafe fn usermode(ip: usize, sp: usize) -> ! {
     // Go to usermode
-    asm!("xchg bx, bx
-        mov ds, ax
+    asm!("mov ds, ax
         mov es, ax
         mov fs, ax
         mov gs, ax