arch/microblaze/kernel/traps.c

   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/sched/debug.h>
  16 #include <linux/debug_locks.h>
  17
  18 #include <asm/exceptions.h>
  19 #include <asm/unwind.h>
  20
  21 void trap_init(void)
  22 {
  23         __enable_hw_exceptions();
  24 }
  25
  26 static unsigned long kstack_depth_to_print;     /* 0 == entire stack */
  27
  28 static int __init kstack_setup(char *s)
  29 {
  30         return !kstrtoul(s, 0, &kstack_depth_to_print);
  31 }
  32 __setup("kstack=", kstack_setup);
  33
  34 void show_stack(struct task_struct *task, unsigned long *sp)
  35 {
  36         unsigned long words_to_show;
  37         u32 fp = (u32) sp;
  38
  39         if (fp == 0) {
  40                 if (task) {
  41                         fp = ((struct thread_info *)
  42                                 (task->stack))->cpu_context.r1;
  43                 } else {
  44                         /* Pick up caller of dump_stack() */
  45                         fp = (u32)&sp - 8;
  46                 }
  47         }
  48
  49         words_to_show = (THREAD_SIZE - (fp & (THREAD_SIZE - 1))) >> 2;
  50         if (kstack_depth_to_print && (words_to_show > kstack_depth_to_print))
  51                 words_to_show = kstack_depth_to_print;
  52
  53         pr_info("Kernel Stack:\n");
  54
  55         /*
  56          * Make the first line an 'odd' size if necessary to get
  57          * remaining lines to start at an address multiple of 0x10
  58          */
  59         if (fp & 0xF) {
  60                 unsigned long line1_words = (0x10 - (fp & 0xF)) >> 2;
  61                 if (line1_words < words_to_show) {
  62                         print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32,
  63                                        4, (void *)fp, line1_words << 2, 0);
  64                         fp += line1_words << 2;
  65                         words_to_show -= line1_words;
  66                 }
  67         }
  68         print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32, 4, (void *)fp,
  69                        words_to_show << 2, 0);
  70         pr_info("\n\nCall Trace:\n");
  71         microblaze_unwind(task, NULL);
  72         pr_info("\n");
  73
  74         if (!task)
  75                 task = current;
  76
  77         debug_show_held_locks(task);
  78 }