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/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 }