Index: kernel/generic/src/syscall/syscall.c
===================================================================
--- kernel/generic/src/syscall/syscall.c	(revision 1e9f8ab55e857ca808bc37b0167fb0a161c48d80)
+++ kernel/generic/src/syscall/syscall.c	(revision 8f5e252705d5ca6f72f60a2ba9d6bbf42b7f7f17)
@@ -45,4 +45,5 @@
 #include <debug.h>
 #include <ddi/device.h>
+#include <interrupt.h>
 #include <ipc/sysipc.h>
 #include <synch/futex.h>
@@ -66,7 +67,13 @@
 #ifdef CONFIG_UDEBUG
 	/*
+	 * An istate_t-compatible record was created on the stack by the
+	 * low-level syscall handler. This is the userspace space state
+	 * structure.
+	 */
+	THREAD->udebug.uspace_state = istate_get(THREAD);
+
+	/*
 	 * Early check for undebugged tasks. We do not lock anything as this
 	 * test need not be precise in either direction.
-	 *
 	 */
 	if (THREAD->udebug.active)
@@ -98,4 +105,7 @@
 		udebug_stoppable_end();
 	}
+
+	/* Clear userspace state pointer */
+	THREAD->udebug.uspace_state = NULL;
 #endif