arch/x86/mm/extable.c

   1 #include <linux/module.h>
   2 #include <linux/spinlock.h>
   3 #include <asm/uaccess.h>
   4
   5
   6 int fixup_exception(struct pt_regs *regs)
   7 {
   8         const struct exception_table_entry *fixup;
   9
  10 #ifdef CONFIG_PNPBIOS
  11         if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) {
  12                 extern u32 pnp_bios_fault_eip, pnp_bios_fault_esp;
  13                 extern u32 pnp_bios_is_utter_crap;
  14                 pnp_bios_is_utter_crap = 1;
  15                 printk(KERN_CRIT "PNPBIOS fault.. attempting recovery.\n");
  16                 __asm__ volatile(
  17                         "movl %0, %%esp\n\t"
  18                         "jmp *%1\n\t"
  19                         : : "g" (pnp_bios_fault_esp), "g" (pnp_bios_fault_eip));
  20                 panic("do_trap: can't hit this");
  21         }
  22 #endif
  23
  24         fixup = search_exception_tables(regs->ip);
  25         if (fixup) {
  26                 /* If fixup is less than 16, it means uaccess error */
  27                 if (fixup->fixup < 16) {
  28                         current_thread_info()->uaccess_err = -EFAULT;
  29                         regs->ip += fixup->fixup;
  30                         return 1;
  31                 }
  32                 regs->ip = fixup->fixup;
  33                 return 1;
  34         }
  35
  36         return 0;
  37 }