arch/arm/include/asm/bug.h

   1 #ifndef _ASMARM_BUG_H
   2 #define _ASMARM_BUG_H
   3
   4
   5 #ifdef CONFIG_BUG
   6
   7 /*
   8  * Use a suitable undefined instruction to use for ARM/Thumb2 bug handling.
   9  * We need to be careful not to conflict with those used by other modules and
  10  * the register_undef_hook() system.
  11  */
  12 #ifdef CONFIG_THUMB2_KERNEL
  13 #define BUG_INSTR_VALUE 0xde02
  14 #define BUG_INSTR_TYPE ".hword "
  15 #else
  16 #define BUG_INSTR_VALUE 0xe7f001f2
  17 #define BUG_INSTR_TYPE ".word "
  18 #endif
  19
  20
  21 #define BUG() _BUG(__FILE__, __LINE__, BUG_INSTR_VALUE)
  22 #define _BUG(file, line, value) __BUG(file, line, value)
  23
  24 #ifdef CONFIG_DEBUG_BUGVERBOSE
  25
  26 /*
  27  * The extra indirection is to ensure that the __FILE__ string comes through
  28  * OK. Many version of gcc do not support the asm %c parameter which would be
  29  * preferable to this unpleasantness. We use mergeable string sections to
  30  * avoid multiple copies of the string appearing in the kernel image.
  31  */
  32
  33 #define __BUG(__file, __line, __value)                          \
  34 do {                                                            \
  35         BUILD_BUG_ON(sizeof(struct bug_entry) != 12);           \
  36         asm volatile("1:\t" BUG_INSTR_TYPE #__value "\n"        \
  37                 ".pushsection .rodata.str, \"aMS\", %progbits, 1\n" \
  38                 "2:\t.asciz " #__file "\n"                      \
  39                 ".popsection\n"                                 \
  40                 ".pushsection __bug_table,\"a\"\n"              \
  41                 "3:\t.word 1b, 2b\n"                            \
  42                 "\t.hword " #__line ", 0\n"                     \
  43                 ".popsection");                                 \
  44         unreachable();                                          \
  45 } while (0)
  46
  47 #else  /* not CONFIG_DEBUG_BUGVERBOSE */
  48
  49 #define __BUG(__file, __line, __value)                          \
  50 do {                                                            \
  51         asm volatile(BUG_INSTR_TYPE #__value);                  \
  52         unreachable();                                          \
  53 } while (0)
  54 #endif  /* CONFIG_DEBUG_BUGVERBOSE */
  55
  56 #define HAVE_ARCH_BUG
  57 #endif  /* CONFIG_BUG */
  58
  59 #include <asm-generic/bug.h>
  60
  61 #endif