diff --git a/arch/x64/processor.hh b/arch/x64/processor.hh
index 6c3cd6ea227a78435a4d97a6eb2c7725f66d7cb5..93ece95b9b73339322e6af138225309e7dba0182 100644
--- a/arch/x64/processor.hh
+++ b/arch/x64/processor.hh
@@ -202,6 +202,11 @@ inline void wrmsr(u32 index, u64 data) {
     asm volatile ("wrmsr" : : "c"(index), "a"(lo), "d"(hi));
 }
 
+inline void wrfsbase(u64 data)
+{
+    asm volatile("wrfsbase %0" : : "r"(data));
+}
+
 inline void halt_no_interrupts() {
     asm volatile ("cli; hlt");
 }