---

yaml
---
r: 138465
b: refs/heads/master
c: bb72534
h: refs/heads/master
i:
  138463: a5c8210
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 465428884765b43d642a967915e16c6c7cacbe8e
+refs/heads/master: bb7253403f7a4670a128e4c080fd8ea1bd4d5029

trunk/arch/powerpc/kernel/entry_64.S

@@ -970,6 +970,28 @@ _GLOBAL(ftrace_graph_caller)
 	blr
 
 _GLOBAL(return_to_handler)
+	/* need to save return values */
+	std	r4,  -24(r1)
+	std	r3,  -16(r1)
+	std	r31, -8(r1)
+	mr	r31, r1
+	stdu	r1, -112(r1)
+
+	bl	.ftrace_return_to_handler
+	nop
+
+	/* return value has real return address */
+	mtlr	r3
+
+	ld	r1, 0(r1)
+	ld	r4,  -24(r1)
+	ld	r3,  -16(r1)
+	ld	r31, -8(r1)
+
+	/* Jump back to real return address */
+	blr
+
+_GLOBAL(mod_return_to_handler)
 	/* need to save return values */
 	std	r4,  -32(r1)
 	std	r3,  -24(r1)
@@ -979,7 +1001,10 @@ _GLOBAL(return_to_handler)
 	mr	r31, r1
 	stdu	r1, -112(r1)
 
-	/* update the TOC */
+	/*
+	 * We are in a module using the module's TOC.
+	 * Switch to our TOC to run inside the core kernel.
+	 */
 	LOAD_REG_IMMEDIATE(r4,ftrace_return_to_handler)
 	ld	r2, 8(r4)
 

trunk/arch/powerpc/kernel/ftrace.c

@@ -567,6 +567,10 @@ int ftrace_disable_ftrace_graph_caller(void)
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */
 
+#ifdef CONFIG_PPC64
+extern void mod_return_to_handler(void);
+#endif
+
 /*
  * Hook the return address and push it in the stack of return addrs
  * in current thread info.
@@ -577,12 +581,17 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr)
 	unsigned long long calltime;
 	int faulted;
 	struct ftrace_graph_ent trace;
-	unsigned long return_hooker = (unsigned long)
-				&return_to_handler;
+	unsigned long return_hooker = (unsigned long)&return_to_handler;
 
 	if (unlikely(atomic_read(&current->tracing_graph_pause)))
 		return;
 
+#if CONFIG_PPC64
+	/* non core kernel code needs to save and restore the TOC */
+	if (REGION_ID(self_addr) != KERNEL_REGION_ID)
+		return_hooker = (unsigned long)&mod_return_to_handler;
+#endif
+
 	return_hooker = GET_ADDR(return_hooker);
 
 	/*