--- zzzz-none-000/linux-3.10.107/arch/um/kernel/sysrq.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/um/kernel/sysrq.c	2021-02-04 17:41:59.000000000 +0000
@@ -1,6 +1,10 @@
 /*
  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
+ * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
  */
 
 #include <linux/kallsyms.h>
@@ -8,59 +12,48 @@
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <asm/sysrq.h>
+#include <asm/stacktrace.h>
+#include <os.h>
 
-/* Catch non-i386 SUBARCH's. */
-#if !defined(CONFIG_UML_X86) || defined(CONFIG_64BIT)
-void show_trace(struct task_struct *task, unsigned long * stack)
+static void _print_addr(void *data, unsigned long address, int reliable)
 {
-	unsigned long addr;
-
-	if (!stack) {
-		stack = (unsigned long*) &stack;
-		WARN_ON(1);
-	}
-
-	printk(KERN_INFO "Call Trace: \n");
-	while (((long) stack & (THREAD_SIZE-1)) != 0) {
-		addr = *stack;
-		if (__kernel_text_address(addr)) {
-			printk(KERN_INFO "%08lx:  [<%08lx>]",
-			       (unsigned long) stack, addr);
-			print_symbol(KERN_CONT " %s", addr);
-			printk(KERN_CONT "\n");
-		}
-		stack++;
-	}
-	printk(KERN_INFO "\n");
+	pr_info(" [<%08lx>]", address);
+	pr_cont(" %s", reliable ? "" : "? ");
+	print_symbol("%s", address);
+	pr_cont("\n");
 }
-#endif
 
-/*Stolen from arch/i386/kernel/traps.c */
-static const int kstack_depth_to_print = 24;
+static const struct stacktrace_ops stackops = {
+	.address = _print_addr
+};
 
-/* This recently started being used in arch-independent code too, as in
- * kernel/sched.c.*/
-void show_stack(struct task_struct *task, unsigned long *esp)
+void show_stack(struct task_struct *task, unsigned long *stack)
 {
-	unsigned long *stack;
+	unsigned long *sp = stack;
+	struct pt_regs *segv_regs = current->thread.segv_regs;
 	int i;
 
-	if (esp == NULL) {
-		if (task != current && task != NULL) {
-			esp = (unsigned long *) KSTK_ESP(task);
-		} else {
-			esp = (unsigned long *) &esp;
-		}
+	if (!segv_regs && os_is_signal_stack()) {
+		pr_err("Received SIGSEGV in SIGSEGV handler,"
+				" aborting stack trace!\n");
+		return;
 	}
 
-	stack = esp;
-	for (i = 0; i < kstack_depth_to_print; i++) {
+	if (!stack)
+		sp = get_stack_pointer(task, segv_regs);
+
+	pr_info("Stack:\n");
+	stack = sp;
+	for (i = 0; i < 3 * STACKSLOTS_PER_LINE; i++) {
 		if (kstack_end(stack))
 			break;
-		if (i && ((i % 8) == 0))
-			printk(KERN_INFO "       ");
-		printk(KERN_CONT "%08lx ", *stack++);
+		if (i && ((i % STACKSLOTS_PER_LINE) == 0))
+			pr_cont("\n");
+		pr_cont(" %08lx", *stack++);
 	}
+	pr_cont("\n");
 
-	show_trace(task, esp);
+	pr_info("Call Trace:\n");
+	dump_trace(current, &stackops, NULL);
+	pr_info("\n");
 }