From 3ad5319327eb1f076de17c9ad03f6fd58e987e2a Mon Sep 17 00:00:00 2001
From: Johannes Weiner <jw@emlix.com>
Date: Mon, 11 May 2009 15:43:33 +0200
Subject: [PATCH] --- yaml --- r: 144919 b: refs/heads/master c:
 586411dcd1935f91796d5e8a29aa3cfdf01a01f4 h: refs/heads/master i:   144917:
 92e3732943a65166e794d49f4af12203ce4bcab0   144915:
 356ec68f27f49540afe8c3c8cda50b468c97a0a6   144911:
 f18166359655ab326511d0766b5699c6898634eb v: v3

---
 [refs]                           |  2 +-
 trunk/arch/xtensa/kernel/traps.c | 16 ++++++++++++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 5f358c021b1c..260661dc9da4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 7dbe5c542464a511f0ea6a14e3ff08874d7e21d5
+refs/heads/master: 586411dcd1935f91796d5e8a29aa3cfdf01a01f4
diff --git a/trunk/arch/xtensa/kernel/traps.c b/trunk/arch/xtensa/kernel/traps.c
index 9f0b71189e94..ba9ab9349782 100644
--- a/trunk/arch/xtensa/kernel/traps.c
+++ b/trunk/arch/xtensa/kernel/traps.c
@@ -369,6 +369,18 @@ void show_regs(struct pt_regs * regs)
 		       regs->syscall);
 }
 
+static __always_inline unsigned long *stack_pointer(struct task_struct *task)
+{
+	unsigned long *sp;
+
+	if (!task || task == current)
+		__asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp));
+	else
+		sp = (unsigned long *)task->thread.sp;
+
+	return sp;
+}
+
 void show_trace(struct task_struct *task, unsigned long *sp)
 {
 	unsigned long a0, a1, pc;
@@ -377,7 +389,7 @@ void show_trace(struct task_struct *task, unsigned long *sp)
 	if (sp)
 		a1 = (unsigned long)sp;
 	else
-		a1 = task->thread.sp;
+		a1 = (unsigned long)stack_pointer(task);
 
 	sp_start = a1 & ~(THREAD_SIZE-1);
 	sp_end = sp_start + THREAD_SIZE;
@@ -420,7 +432,7 @@ void show_stack(struct task_struct *task, unsigned long *sp)
 	unsigned long *stack;
 
 	if (!sp)
-		sp = (unsigned long *)task->thread.sp;
+		sp = stack_pointer(task);
  	stack = sp;
 
 	printk("\nStack: ");