From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeremy Fitzhardinge <jeremy@goop.org>
Subject: Re: [PATCH] x86/32on64: zero-extend hypercall index before
	use in memory access (debug mode only)
Date: Wed, 15 Dec 2010 14:21:11 -0800
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To: Jan Beulich <JBeulich@novell.com>
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On 12/15/2010 02:50 AM, Jan Beulich wrote:
> Signed-off-by: Jan Beulich <jbeulich@novell.com>
>
> --- a/xen/arch/x86/x86_64/compat/entry.S
> +++ b/xen/arch/x86/x86_64/compat/entry.S
> @@ -25,7 +25,8 @@ ENTRY(compat_hypercall)
>          pushq UREGS_rbx(%rsp); pushq %rcx; pushq %rdx; pushq %rsi; pushq %rdi
>          pushq UREGS_rbp+5*8(%rsp)
>          leaq  compat_hypercall_args_table(%rip),%r10
> -        movq  $6,%rcx
> +        movl  %eax,%eax
> +        movl  $6,%ecx

Is the second line part of the fix, or just a drive-by tweak?

    J