63 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			63 lines
		
	
	
	
		
			1.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | #include <linux/module.h>
 | ||
|  | #include <linux/spinlock.h>
 | ||
|  | #include <asm/uaccess.h>
 | ||
|  | 
 | ||
|  | 
 | ||
|  | int fixup_exception(struct pt_regs *regs) | ||
|  | { | ||
|  | 	const struct exception_table_entry *fixup; | ||
|  | 
 | ||
|  | #ifdef CONFIG_PNPBIOS
 | ||
|  | 	if (unlikely(SEGMENT_IS_PNP_CODE(regs->cs))) { | ||
|  | 		extern u32 pnp_bios_fault_eip, pnp_bios_fault_esp; | ||
|  | 		extern u32 pnp_bios_is_utter_crap; | ||
|  | 		pnp_bios_is_utter_crap = 1; | ||
|  | 		printk(KERN_CRIT "PNPBIOS fault.. attempting recovery.\n"); | ||
|  | 		__asm__ volatile( | ||
|  | 			"movl %0, %%esp\n\t" | ||
|  | 			"jmp *%1\n\t" | ||
|  | 			: : "g" (pnp_bios_fault_esp), "g" (pnp_bios_fault_eip)); | ||
|  | 		panic("do_trap: can't hit this"); | ||
|  | 	} | ||
|  | #endif
 | ||
|  | 
 | ||
|  | 	fixup = search_exception_tables(regs->ip); | ||
|  | 	if (fixup) { | ||
|  | 		regs->ip = fixup->fixup; | ||
|  | 		return 1; | ||
|  | 	} | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | #ifdef CONFIG_X86_64
 | ||
|  | /*
 | ||
|  |  * Need to defined our own search_extable on X86_64 to work around | ||
|  |  * a B stepping K8 bug. | ||
|  |  */ | ||
|  | const struct exception_table_entry * | ||
|  | search_extable(const struct exception_table_entry *first, | ||
|  | 	       const struct exception_table_entry *last, | ||
|  | 	       unsigned long value) | ||
|  | { | ||
|  | 	/* B stepping K8 bug */ | ||
|  | 	if ((value >> 32) == 0) | ||
|  | 		value |= 0xffffffffUL << 32; | ||
|  | 
 | ||
|  | 	while (first <= last) { | ||
|  | 		const struct exception_table_entry *mid; | ||
|  | 		long diff; | ||
|  | 
 | ||
|  | 		mid = (last - first) / 2 + first; | ||
|  | 		diff = mid->insn - value; | ||
|  | 		if (diff == 0) | ||
|  | 			return mid; | ||
|  | 		else if (diff < 0) | ||
|  | 			first = mid+1; | ||
|  | 		else | ||
|  | 			last = mid-1; | ||
|  | 	} | ||
|  | 	return NULL; | ||
|  | } | ||
|  | #endif
 |