xref: /linux/arch/microblaze/kernel/traps.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
1 /*
2  * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
3  * Copyright (C) 2007-2009 PetaLogix
4  * Copyright (C) 2006 Atmark Techno, Inc.
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License. See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 
11 #include <linux/export.h>
12 #include <linux/kernel.h>
13 #include <linux/kallsyms.h>
14 #include <linux/sched.h>
15 #include <linux/debug_locks.h>
16 
17 #include <asm/exceptions.h>
18 #include <asm/unwind.h>
19 
20 void trap_init(void)
21 {
22 	__enable_hw_exceptions();
23 }
24 
25 static unsigned long kstack_depth_to_print;	/* 0 == entire stack */
26 
27 static int __init kstack_setup(char *s)
28 {
29 	return !kstrtoul(s, 0, &kstack_depth_to_print);
30 }
31 __setup("kstack=", kstack_setup);
32 
33 void show_stack(struct task_struct *task, unsigned long *sp)
34 {
35 	unsigned long words_to_show;
36 	u32 fp = (u32) sp;
37 
38 	if (fp == 0) {
39 		if (task) {
40 			fp = ((struct thread_info *)
41 				(task->stack))->cpu_context.r1;
42 		} else {
43 			/* Pick up caller of dump_stack() */
44 			fp = (u32)&sp - 8;
45 		}
46 	}
47 
48 	words_to_show = (THREAD_SIZE - (fp & (THREAD_SIZE - 1))) >> 2;
49 	if (kstack_depth_to_print && (words_to_show > kstack_depth_to_print))
50 		words_to_show = kstack_depth_to_print;
51 
52 	pr_info("Kernel Stack:\n");
53 
54 	/*
55 	 * Make the first line an 'odd' size if necessary to get
56 	 * remaining lines to start at an address multiple of 0x10
57 	 */
58 	if (fp & 0xF) {
59 		unsigned long line1_words = (0x10 - (fp & 0xF)) >> 2;
60 		if (line1_words < words_to_show) {
61 			print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32,
62 				       4, (void *)fp, line1_words << 2, 0);
63 			fp += line1_words << 2;
64 			words_to_show -= line1_words;
65 		}
66 	}
67 	print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32, 4, (void *)fp,
68 		       words_to_show << 2, 0);
69 	pr_info("\n\nCall Trace:\n");
70 	microblaze_unwind(task, NULL);
71 	pr_info("\n");
72 
73 	if (!task)
74 		task = current;
75 
76 	debug_show_held_locks(task);
77 }
78