From 5c048120064fce7ee7c28d2515eff50809506348 Mon Sep 17 00:00:00 2001
From: Kevin Hao <kexin.hao@windriver.com>
Date: Thu, 10 Nov 2011 16:04:17 +0000
Subject: [PATCH] --- yaml --- r: 275544 b: refs/heads/master c:
 2cd76629f6c40f7b227ba7b3885ce10e6ec0face h: refs/heads/master v: v3

---
 [refs]                               |  2 +-
 trunk/arch/powerpc/kernel/entry_32.S | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 3fa358f34a4c..c0f8fbf4ab06 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d715e433b7ad19c02fc4becf0d5e9a59f97925de
+refs/heads/master: 2cd76629f6c40f7b227ba7b3885ce10e6ec0face
diff --git a/trunk/arch/powerpc/kernel/entry_32.S b/trunk/arch/powerpc/kernel/entry_32.S
index 56212bc0ab08..4f80cf1ce77b 100644
--- a/trunk/arch/powerpc/kernel/entry_32.S
+++ b/trunk/arch/powerpc/kernel/entry_32.S
@@ -215,7 +215,22 @@ reenable_mmu:				/* re-enable mmu so we can */
 	stw	r9,8(r1)
 	stw	r11,12(r1)
 	stw	r3,ORIG_GPR3(r1)
+	/*
+	 * The trace_hardirqs_off will use CALLER_ADDR0 and CALLER_ADDR1.
+	 * If from user mode there is only one stack frame on the stack, and
+	 * accessing CALLER_ADDR1 will cause oops. So we need create a dummy
+	 * stack frame to make trace_hardirqs_off happy.
+	 */
+	andi.	r12,r12,MSR_PR
+	beq	11f
+	stwu	r1,-16(r1)
+	bl	trace_hardirqs_off
+	addi	r1,r1,16
+	b	12f
+
+11:
 	bl	trace_hardirqs_off
+12:
 	lwz	r0,GPR0(r1)
 	lwz	r3,ORIG_GPR3(r1)
 	lwz	r4,GPR4(r1)