Re: [PATCH 1/2]KVM: x86_emulator: Decode the memory operand for 'mov'

[Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>]

Yang, Sheng wrote:
> >From ebfc23b71051e5ab19d22fb3f9c3d57721566ea9 Mon Sep 17 00:00:00 2001
> From: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Date: Fri, 26 Oct 2007 13:41:28 +0800
> Subject: [PATCH] KVM: x86_emulator: Decode the memory operand for 'mov'
>
> For the following TPR patch, we must get gva for executing instructions.
> Most
> memory operands are decoded in ModR/M part, except some kinds of 'mov'.
> This
> patch decoded the memory operand for these 'mov' instructions, instead
> of using
> CR2.
>
> Signed-off-by: Sheng Yang <sheng.yang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> ---
>  drivers/kvm/x86_emulate.c |   11 +++++++++++
>  1 files changed, 11 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c
> index f858c01..f75f75a 100644
> --- a/drivers/kvm/x86_emulate.c
> +++ b/drivers/kvm/x86_emulate.c
> @@ -837,6 +837,11 @@ modrm_done:
>  				    && c->modrm_reg == 7)
>  			break;
>  	      srcmem_common:
> +		/* Decode memory operand for mov(0xa0 ... 0xa1)*/
> +		if ((c->b == 0xa0) || (c->b == 0xa1)) {
> +			ctxt->cr2 = insn_fetch(u32, c->src.bytes,
> c->eip);
> +			c->eip -= c->src.bytes;
> +		}
>   

We're moving eip backwards here, then forwards in x86_emulate_insn()... 
I'm getting dizzy.

How about add a MemAbs bitflag in decode it outside, similar to the 
ModRM flag and decoding?


-- 
error compiling committee.c: too many arguments to function


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