xref: /openbmc/linux/arch/x86/mm/extable.c (revision 7dd65feb)
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 }
38