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/cpu.h>
  12 #include <linux/export.h>
  13 #include <linux/kernel.h>
  14 #include <linux/kallsyms.h>
  15 #include <linux/sched.h>
  16 #include <linux/sched/debug.h>
  17 #include <linux/debug_locks.h>
  18
  19 #include <asm/exceptions.h>
  20 #include <asm/unwind.h>
  21
  22 void trap_init(void)
  23 {
  24         __enable_hw_exceptions();
  25 }
  26
  27 static unsigned long kstack_depth_to_print;     /* 0 == entire stack */
  28
  29 static int __init kstack_setup(char *s)
  30 {
  31         return !kstrtoul(s, 0, &kstack_depth_to_print);
  32 }
  33 __setup("kstack=", kstack_setup);
  34
  35 void show_stack(struct task_struct *task, unsigned long *sp, const char *loglvl)
  36 {
  37         unsigned long words_to_show;
  38         u32 fp = (u32) sp;
  39
  40         if (fp == 0) {
  41                 if (task) {
  42                         fp = ((struct thread_info *)
  43                                 (task->stack))->cpu_context.r1;
  44                 } else {
  45                         /* Pick up caller of dump_stack() */
  46                         fp = (u32)&sp - 8;
  47                 }
  48         }
  49
  50         words_to_show = (THREAD_SIZE - (fp & (THREAD_SIZE - 1))) >> 2;
  51         if (kstack_depth_to_print && (words_to_show > kstack_depth_to_print))
  52                 words_to_show = kstack_depth_to_print;
  53
  54         printk("%sKernel Stack:\n", loglvl);
  55
  56         /*
  57          * Make the first line an 'odd' size if necessary to get
  58          * remaining lines to start at an address multiple of 0x10
  59          */
  60         if (fp & 0xF) {
  61                 unsigned long line1_words = (0x10 - (fp & 0xF)) >> 2;
  62                 if (line1_words < words_to_show) {
  63                         print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 32,
  64                                        4, (void *)fp, line1_words << 2, 0);
  65                         fp += line1_words << 2;
  66                         words_to_show -= line1_words;
  67                 }
  68         }
  69         print_hex_dump(loglvl, "", DUMP_PREFIX_ADDRESS, 32, 4, (void *)fp,
  70                        words_to_show << 2, 0);
  71         printk("%s\n\nCall Trace:\n", loglvl);
  72         microblaze_unwind(task, NULL, loglvl);
  73         printk("%s\n", loglvl);
  74
  75         if (!task)
  76                 task = current;
  77
  78         debug_show_held_locks(task);
  79 }