diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index d0074c6ed31a38ba1778bc776f857a6088b943d3..fad8faa29d042d59ab9ae0f6d89d7aaee5b8a041 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -149,7 +149,7 @@ is_prefetch(struct pt_regs *regs, unsigned long error_code, unsigned long addr)
 		unsigned char opcode;
 
 		if (user_mode(regs)) {
-			if (get_user(opcode, instr))
+			if (get_user(opcode, (unsigned char __user *) instr))
 				break;
 		} else {
 			if (get_kernel_nofault(opcode, instr))