Re: [Patch 7/7] RealMode: Adds support for mov r, sreg (0x8c) instruction

[Avi Kivity <avi@qumranet.com>]

Guillaume Thouvenin wrote:
> Adds support for mov r, sreg (0x8c) instruction
>
> Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
> Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
>
> ---
>  arch/x86/kvm/x86_emulate.c |   21 ++++++++++++++++++++-
>  1 files changed, 20 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kvm/x86_emulate.c b/arch/x86/kvm/x86_emulate.c
> index 106d714..35767e7 100644
> --- a/arch/x86/kvm/x86_emulate.c
> +++ b/arch/x86/kvm/x86_emulate.c
> @@ -138,7 +138,7 @@ static u16 opcode_table[256] = {
>  	/* 0x88 - 0x8F */
>  	ByteOp | DstMem | SrcReg | ModRM | Mov, DstMem | SrcReg | ModRM | Mov,
>  	ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
> -	0, ModRM | DstReg,
> +	DstMem | SrcReg | ModRM | Mov, ModRM | DstReg,
>  	DstReg | SrcMem | ModRM | Mov, Group | Group1A,
>  	/* 0x90 - 0x9F */
>  	0, 0, 0, 0, 0, 0, 0, 0,
> @@ -1531,6 +1531,25 @@ special_insn:
>  		break;
>  	case 0x88 ... 0x8b:	/* mov */
>  		goto mov;
> +	case 0x8c: { /* mov r/m, sreg */
> +		struct kvm_segment segreg;
> +
> +		if (c->modrm_mod == 0x3)
> +			c->src.val = c->modrm_val;
>   

What's this bit?

> +
> +		if (c->modrm_reg <= 5)
> +			kvm_get_segment(ctxt->vcpu, &segreg, vcpu_sreg_table[c->modrm_reg]);
> +		else {
> +			printk(KERN_INFO "0x8c: Invalid segreg in modrm byte 0x%02x\n",
> +					 c->modrm);
> +			goto cannot_emulate;
> +		}
> +		c->dst.val = segreg.selector;
> +		c->dst.bytes = 2;
> +		c->dst.ptr = (unsigned long *)decode_register(c->modrm_rm, c->regs,
> +							      c->d & ByteOp);
>   

Aren't dst.bytes and dst.ptr already set by the decoder?

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