[PATCH] parisc: better stack traces

In parisc_terminate(), do the stack trace from the faulting location
instead of from the current (i.e. parisc_terminate()) location.
Committed-by: Randolph Chung <tausq@parisc-linux.org>

arch/parisc/kernel/traps.c

@@ -135,32 +135,19 @@ void dump_stack(void)
 
 EXPORT_SYMBOL(dump_stack);
 
-void show_stack(struct task_struct *task, unsigned long *s)
+static void do_show_stack(struct unwind_frame_info *info)
 {
 	int i = 1;
-	struct unwind_frame_info info;
-
-	if (!task) {
-		unsigned long sp, ip, rp;
-
-HERE:
-		asm volatile ("copy %%r30, %0" : "=r"(sp));
-		ip = (unsigned long)&&HERE;
-		rp = (unsigned long)__builtin_return_address(0);
-		unwind_frame_init(&info, current, sp, ip, rp);
-	} else {
-		unwind_frame_init_from_blocked_task(&info, task);
-	}
 
 	printk("Backtrace:\n");
 	while (i <= 16) {
-		if (unwind_once(&info) < 0 || info.ip == 0)
+		if (unwind_once(info) < 0 || info->ip == 0)
 			break;
 
-		if (__kernel_text_address(info.ip)) {
-			printk(" [<" RFMT ">] ", info.ip);
+		if (__kernel_text_address(info->ip)) {
+			printk(" [<" RFMT ">] ", info->ip);
 #ifdef CONFIG_KALLSYMS
-			print_symbol("%s\n", info.ip);
+			print_symbol("%s\n", info->ip);
 #else
 			if ((i & 0x03) == 0)
 				printk("\n");
@@ -171,6 +158,25 @@ void show_stack(struct task_struct *task, unsigned long *s)
 	printk("\n");
 }
 
+void show_stack(struct task_struct *task, unsigned long *s)
+{
+	struct unwind_frame_info info;
+
+	if (!task) {
+		unsigned long sp, ip, rp;
+
+HERE:
+		asm volatile ("copy %%r30, %0" : "=r"(sp));
+		ip = (unsigned long)&&HERE;
+		rp = (unsigned long)__builtin_return_address(0);
+		unwind_frame_init(&info, current, sp, ip, rp);
+	} else {
+		unwind_frame_init_from_blocked_task(&info, task);
+	}
+
+	do_show_stack(&info);
+}
+
 void die_if_kernel(char *str, struct pt_regs *regs, long err)
 {
 	if (user_mode(regs)) {
@@ -407,7 +413,12 @@ void parisc_terminate(char *msg, struct pt_regs *regs, int code, unsigned long o
 
 	}
 	    
-	show_stack(NULL, (unsigned long *)regs->gr[30]);
+	{
+		/* show_stack(NULL, (unsigned long *)regs->gr[30]); */
+		struct unwind_frame_info info;
+		unwind_frame_init(&info, current, regs->gr[30], regs->iaoq[0], regs->gr[2]);
+		do_show_stack(&info);
+	}
 
 	printk("\n");
 	printk(KERN_CRIT "%s: Code=%d regs=%p (Addr=" RFMT ")\n",