Index: kernel/generic/include/main/uinit.h
===================================================================
--- kernel/generic/include/main/uinit.h	(revision 096c0786530d26ecc60b3c63b61e396df267c704)
+++ kernel/generic/include/main/uinit.h	(revision 513237966a1ea4b66980df2deb5b151213666dae)
@@ -36,4 +36,11 @@
 #define KERN_UINIT_H_
 
+#include <stdint.h>
+
+typedef struct {
+	uintptr_t pc;
+	uintptr_t sp;
+} uinit_arg_t;
+
 extern void uinit(void *arg);
 
Index: kernel/generic/include/proc/thread.h
===================================================================
--- kernel/generic/include/proc/thread.h	(revision 096c0786530d26ecc60b3c63b61e396df267c704)
+++ kernel/generic/include/proc/thread.h	(revision 513237966a1ea4b66980df2deb5b151213666dae)
@@ -45,5 +45,4 @@
 #include <arch/cpu.h>
 #include <mm/tlb.h>
-#include <abi/proc/uarg.h>
 #include <udebug/udebug.h>
 #include <abi/proc/thread.h>
Index: kernel/generic/include/userspace.h
===================================================================
--- kernel/generic/include/userspace.h	(revision 096c0786530d26ecc60b3c63b61e396df267c704)
+++ kernel/generic/include/userspace.h	(revision 513237966a1ea4b66980df2deb5b151213666dae)
@@ -39,6 +39,8 @@
 #include <typedefs.h>
 
+extern uintptr_t arch_get_initial_sp(uintptr_t stack_base, uintptr_t stack_size);
+
 /** Switch to user-space (CPU user priviledge level) */
-extern void userspace(uspace_arg_t *uarg) __attribute__((noreturn));
+extern void userspace(sysarg_t pc, sysarg_t sp) __attribute__((noreturn));
 
 #endif