xref: /openbmc/linux/arch/um/kernel/sysrq.c (revision 7587cdef)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4  * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
5  */
6 
7 #include <linux/kallsyms.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/sched.h>
11 #include <linux/sched/debug.h>
12 #include <linux/sched/task_stack.h>
13 
14 #include <asm/sysrq.h>
15 #include <asm/stacktrace.h>
16 #include <os.h>
17 
18 static void _print_addr(void *data, unsigned long address, int reliable)
19 {
20 	const char *loglvl = data;
21 
22 	printk("%s [<%08lx>] %s%pS\n", loglvl, address, reliable ? "" : "? ",
23 		(void *)address);
24 }
25 
26 static const struct stacktrace_ops stackops = {
27 	.address = _print_addr
28 };
29 
30 void show_stack(struct task_struct *task, unsigned long *stack,
31 		       const char *loglvl)
32 {
33 	struct pt_regs *segv_regs = current->thread.segv_regs;
34 	int i;
35 
36 	if (!segv_regs && os_is_signal_stack()) {
37 		pr_err("Received SIGSEGV in SIGSEGV handler,"
38 				" aborting stack trace!\n");
39 		return;
40 	}
41 
42 	if (!stack)
43 		stack = get_stack_pointer(task, segv_regs);
44 
45 	printk("%sStack:\n", loglvl);
46 	for (i = 0; i < 3 * STACKSLOTS_PER_LINE; i++) {
47 		if (kstack_end(stack))
48 			break;
49 		if (i && ((i % STACKSLOTS_PER_LINE) == 0))
50 			pr_cont("\n");
51 		pr_cont(" %08lx", READ_ONCE_NOCHECK(*stack));
52 		stack++;
53 	}
54 
55 	printk("%sCall Trace:\n", loglvl);
56 	dump_trace(current, &stackops, (void *)loglvl);
57 }
58