disable interrupts while locked

src/sync.c

@@ -1,11 +1,13 @@
 #include "sync.h"
 
 void spin_lock(struct spinlock *s) {
+    __asm__ ("cli" :: );
     while (atomic_exchange_explicit(&s->lock, 1, memory_order_acquire)) {
-        // spin
+        __asm__ ("pause" :: );
     }
 }
 
 void spin_unlock(struct spinlock *s) {
     atomic_store_explicit(&s->lock, 0, memory_order_release);
+    __asm__ ("sti" :: );
 }