include/asm-x86_64/bug.h

   1 #ifndef __ASM_X8664_BUG_H
   2 #define __ASM_X8664_BUG_H 1
   3
   4 #include <linux/stringify.h>
   5
   6 /*
   7  * Tell the user there is some problem.  The exception handler decodes
   8  * this frame.
   9  */
  10 struct bug_frame {
  11         unsigned char ud2[2];
  12         unsigned char push;
  13         signed int filename;
  14         unsigned char ret;
  15         unsigned short line;
  16 } __attribute__((packed));
  17
  18 #ifdef CONFIG_BUG
  19 #define HAVE_ARCH_BUG
  20 /* We turn the bug frame into valid instructions to not confuse
  21    the disassembler. Thanks to Jan Beulich & Suresh Siddha
  22    for nice instruction selection.
  23    The magic numbers generate mov $64bitimm,%eax ; ret $offset. */
  24 #define BUG()                                                           \
  25         asm volatile(                                                   \
  26         "ud2 ; pushq $%c1 ; ret $%c0" ::                                \
  27                      "i"(__LINE__), "i" (__FILE__))
  28 void out_of_line_bug(void);
  29 #else
  30 static inline void out_of_line_bug(void) { }
  31 #endif
  32
  33 #include <asm-generic/bug.h>
  34 #endif