Fix 32bit strace for 6 argument system calls

Need to put the argument into ebp on the stack frame.

Originally noted by Roland McGrath 

Index: linux/arch/x86_64/ia32/ia32entry.S
===================================================================
--- linux.orig/arch/x86_64/ia32/ia32entry.S
+++ linux/arch/x86_64/ia32/ia32entry.S
@@ -102,20 +102,18 @@ sysenter_do_call:	
 	.byte	0xf, 0x35
 
 sysenter_tracesys:
+	xchgq	%r9,%rbp
 	SAVE_REST
 	CLEAR_RREGS
 	movq	$-ENOSYS,RAX(%rsp)	/* really needed? */
 	movq	%rsp,%rdi        /* &pt_regs -> arg1 */
+	pushq   %r9
 	call	syscall_trace_enter
+	popq	%r9
 	LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
 	RESTORE_REST
+	xchgq	%rbp,%r9
 	movl	%ebp, %ebp
-	/* no need to do an access_ok check here because rbp has been
-	   32bit zero extended */ 
-1:	movl	(%rbp),%r9d
-	.section __ex_table,"a"
-	.quad 1b,ia32_badarg
-	.previous
 	jmp	sysenter_do_call
 	CFI_ENDPROC
 
@@ -183,20 +181,18 @@ cstar_do_call:	
 	sysretl
 	
 cstar_tracesys:	
+	xchgq %r9,%rbp
 	SAVE_REST
 	CLEAR_RREGS
 	movq $-ENOSYS,RAX(%rsp)	/* really needed? */
 	movq %rsp,%rdi        /* &pt_regs -> arg1 */
+	pushq %r9
 	call syscall_trace_enter
+	popq %r9
 	LOAD_ARGS ARGOFFSET  /* reload args from stack in case ptrace changed it */
 	RESTORE_REST
-	movl RSP-ARGOFFSET(%rsp), %r8d
-	/* no need to do an access_ok check here because r8 has been
-	   32bit zero extended */ 
-1:	movl	(%r8),%r9d
-	.section __ex_table,"a"
-	.quad 1b,ia32_badarg
-	.previous
+	xchgq %r9,%rbp
+	movl %ebp,%ebp
 	jmp cstar_do_call
 				
 ia32_badarg: