Index: kernel/generic/src/interrupt/interrupt.c
===================================================================
--- kernel/generic/src/interrupt/interrupt.c	(revision 5e984f296b2eda2b4b5d68452cfbc8c1134ca2c7)
+++ kernel/generic/src/interrupt/interrupt.c	(revision cd98e5946d71afa0ebd5f598f85d8dee47600539)
@@ -93,6 +93,9 @@
 
 	/* Account user cycles */
-	if (THREAD)
+	if (THREAD) {
+		spinlock_lock(&THREAD->lock);
 		thread_update_accounting(true);
+		spinlock_unlock(&THREAD->lock);
+	}
 
 #ifdef CONFIG_UDEBUG
@@ -110,6 +113,9 @@
 		thread_exit();
 
-	if (THREAD)
+	if (THREAD) {
+		spinlock_lock(&THREAD->lock);
 		thread_update_accounting(false);
+		spinlock_unlock(&THREAD->lock);
+	}
 }