Index: kernel/arch/ppc32/src/ppc32.c
===================================================================
--- kernel/arch/ppc32/src/ppc32.c	(revision 2e533d6f9fc70bcde4836ba05d892f0033109f3b)
+++ kernel/arch/ppc32/src/ppc32.c	(revision 1f092d9ee54c991d7f2820ce325e6374d85b3a26)
@@ -269,5 +269,6 @@
 {
 	userspace_asm((uintptr_t) kernel_uarg->uspace_uarg,
-	    (uintptr_t) kernel_uarg->uspace_stack + STACK_SIZE - SP_DELTA,
+	    (uintptr_t) kernel_uarg->uspace_stack +
+	    kernel_uarg->uspace_stack_size - SP_DELTA,
 	    (uintptr_t) kernel_uarg->uspace_entry);