diff --git a/arch/x86/lib/getuser_64.S b/arch/x86/lib/getuser_64.S
index 5448876261f8..2b003d313480 100644
--- a/arch/x86/lib/getuser_64.S
+++ b/arch/x86/lib/getuser_64.S
@@ -36,10 +36,10 @@
 	.text
 ENTRY(__get_user_1)
 	CFI_STARTPROC
-	GET_THREAD_INFO(%r8)
-	cmpq threadinfo_addr_limit(%r8),%rcx
+	GET_THREAD_INFO(%rdx)
+	cmpq threadinfo_addr_limit(%rdx),%rax
 	jae bad_get_user
-1:	movzb (%rcx),%edx
+1:	movzb (%rax),%edx
 	xorl %eax,%eax
 	ret
 	CFI_ENDPROC
@@ -47,48 +47,48 @@ ENDPROC(__get_user_1)
 
 ENTRY(__get_user_2)
 	CFI_STARTPROC
-	GET_THREAD_INFO(%r8)
-	addq $1,%rcx
+	GET_THREAD_INFO(%rdx)
+	addq $1,%rax
 	jc 20f
-	cmpq threadinfo_addr_limit(%r8),%rcx
+	cmpq threadinfo_addr_limit(%rdx),%rax
 	jae 20f
-	decq   %rcx
-2:	movzwl (%rcx),%edx
+	decq   %rax
+2:	movzwl (%rax),%edx
 	xorl %eax,%eax
 	ret
-20:	decq    %rcx
+20:	decq    %rax
 	jmp	bad_get_user
 	CFI_ENDPROC
 ENDPROC(__get_user_2)
 
 ENTRY(__get_user_4)
 	CFI_STARTPROC
-	GET_THREAD_INFO(%r8)
-	addq $3,%rcx
+	GET_THREAD_INFO(%rdx)
+	addq $3,%rax
 	jc 30f
-	cmpq threadinfo_addr_limit(%r8),%rcx
+	cmpq threadinfo_addr_limit(%rdx),%rax
 	jae 30f
-	subq $3,%rcx
-3:	movl (%rcx),%edx
+	subq $3,%rax
+3:	movl (%rax),%edx
 	xorl %eax,%eax
 	ret
-30:	subq $3,%rcx
+30:	subq $3,%rax
 	jmp bad_get_user
 	CFI_ENDPROC
 ENDPROC(__get_user_4)
 
 ENTRY(__get_user_8)
 	CFI_STARTPROC
-	GET_THREAD_INFO(%r8)
-	addq $7,%rcx
+	GET_THREAD_INFO(%rdx)
+	addq $7,%rax
 	jc 40f
-	cmpq threadinfo_addr_limit(%r8),%rcx
+	cmpq threadinfo_addr_limit(%rdx),%rax
 	jae	40f
-	subq	$7,%rcx
-4:	movq (%rcx),%rdx
+	subq	$7,%rax
+4:	movq (%rax),%rdx
 	xorl %eax,%eax
 	ret
-40:	subq $7,%rcx
+40:	subq $7,%rax
 	jmp bad_get_user
 	CFI_ENDPROC
 ENDPROC(__get_user_8)
diff --git a/include/asm-x86/uaccess_64.h b/include/asm-x86/uaccess_64.h
index b8a2f4339903..a2d49078e19c 100644
--- a/include/asm-x86/uaccess_64.h
+++ b/include/asm-x86/uaccess_64.h
@@ -90,8 +90,7 @@ extern int fixup_exception(struct pt_regs *regs);
 #define __get_user_x(size, ret, x, ptr)		      \
 	asm volatile("call __get_user_" #size	      \
 		     : "=a" (ret),"=d" (x)	      \
-		     : "c" (ptr)		      \
-		     : "r8")
+		     : "0" (ptr))		      \
 
 /* Careful: we have to cast the result to the type of the pointer
  * for sign reasons */