diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index c3fdb3081d3d..47f0dd9a45ad 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -186,8 +186,8 @@ ret_from_fork:
 	li	r3,0	/* fork() return value */
 	b	ret_from_syscall
 
-	.globl	ret_from_kernel_thread
-ret_from_kernel_thread:
+	.globl	ret_from_kernel_user_thread
+ret_from_kernel_user_thread:
 	bl	schedule_tail
 	mtctr	r14
 	mr	r3,r15
@@ -196,6 +196,22 @@ ret_from_kernel_thread:
 	li	r3,0
 	b	ret_from_syscall
 
+	.globl	start_kernel_thread
+start_kernel_thread:
+	bl	schedule_tail
+	mtctr	r14
+	mr	r3,r15
+	PPC440EP_ERR42
+	bctrl
+	/*
+	 * This must not return. We actually want to BUG here, not WARN,
+	 * because BUG will exit the process which is what the kernel thread
+	 * should have done, which may give some hope of continuing.
+	 */
+100:	trap
+	EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,0
+
+
 /*
  * This routine switches between two different tasks.  The process
  * state of one is saved on its kernel stack.  Then the state
diff --git a/arch/powerpc/kernel/interrupt_64.S b/arch/powerpc/kernel/interrupt_64.S
index bac1f89501ac..a44c8aab63ec 100644
--- a/arch/powerpc/kernel/interrupt_64.S
+++ b/arch/powerpc/kernel/interrupt_64.S
@@ -739,7 +739,7 @@ _GLOBAL(ret_from_fork)
 	li	r3,0	/* fork() return value */
 	b	.Lsyscall_exit
 
-_GLOBAL(ret_from_kernel_thread)
+_GLOBAL(ret_from_kernel_user_thread)
 	bl	schedule_tail
 	mtctr	r14
 	mr	r3,r15
@@ -749,3 +749,19 @@ _GLOBAL(ret_from_kernel_thread)
 	bctrl
 	li	r3,0
 	b	.Lsyscall_exit
+
+_GLOBAL(start_kernel_thread)
+	bl	schedule_tail
+	mtctr	r14
+	mr	r3,r15
+#ifdef CONFIG_PPC64_ELF_ABI_V2
+	mr	r12,r14
+#endif
+	bctrl
+	/*
+	 * This must not return. We actually want to BUG here, not WARN,
+	 * because BUG will exit the process which is what the kernel thread
+	 * should have done, which may give some hope of continuing.
+	 */
+100:	trap
+	EMIT_BUG_ENTRY 100b,__FILE__,__LINE__,0
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 88898ca7ab0b..14fe4702a098 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1741,7 +1741,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 	struct pt_regs *kregs; /* Switch frame regs */
 	extern void ret_from_fork(void);
 	extern void ret_from_fork_scv(void);
-	extern void ret_from_kernel_thread(void);
+	extern void ret_from_kernel_user_thread(void);
+	extern void start_kernel_thread(void);
 	void (*f)(void);
 	unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE;
 	struct thread_info *ti = task_thread_info(p);
@@ -1758,7 +1759,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 		sp -= STACK_FRAME_MIN_SIZE;
 		((unsigned long *)sp)[0] = 0;
 
-		f = ret_from_kernel_thread;
+		f = start_kernel_thread;
 		p->thread.regs = NULL;	/* no user register state */
 		clear_tsk_compat_task(p);
 	} else {
@@ -1784,7 +1785,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
 			childregs->softe = IRQS_ENABLED;
 #endif
 			ti->flags |= _TIF_RESTOREALL;
-			f = ret_from_kernel_thread;
+			f = ret_from_kernel_user_thread;
 		} else {
 			struct pt_regs *regs = current_pt_regs();
 			unsigned long clone_flags = args->flags;