Re: [PATCH] KVM: x86 emulator: emulate RETF imm

[Gleb Natapov <gleb@redhat.com>]

On Mon, Sep 09, 2013 at 07:09:15AM -0600, Bruce Rogers wrote:
>  >>> On 9/8/2013 at 07:13 AM, Gleb Natapov <gleb@redhat.com> wrote: 
> > On Tue, Sep 03, 2013 at 01:42:09PM -0600, Bruce Rogers wrote:
> >> Opcode CA
> >> 
> >> This gets used by a DOS based NetWare guest.
> >> 
> >> Signed-off-by: Bruce Rogers <brogers@suse.com>
> >> ---
> >>  arch/x86/kvm/emulate.c |   23 ++++++++++++++++++++++-
> >>  1 files changed, 22 insertions(+), 1 deletions(-)
> >> 
> >> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
> >> index 2bc1e81..aee238a 100644
> >> --- a/arch/x86/kvm/emulate.c
> >> +++ b/arch/x86/kvm/emulate.c
> >> @@ -2025,6 +2025,26 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt)
> >>  	return rc;
> >>  }
> >>  
> >> +static int em_ret_far_imm(struct x86_emulate_ctxt *ctxt)
> >> +{
> >> +        int rc;
> >> +        unsigned long cs;
> >> +
> >> +        rc = emulate_pop(ctxt, &ctxt->_eip, ctxt->op_bytes);
> >> +        if (rc != X86EMUL_CONTINUE)
> >> +                return rc;
> >> +        if (ctxt->op_bytes == 4)
> >> +                ctxt->_eip = (u32)ctxt->_eip;
> >> +        rc = emulate_pop(ctxt, &cs, ctxt->op_bytes);
> >> +        if (rc != X86EMUL_CONTINUE)
> >> +                return rc;
> >> +        rc = load_segment_descriptor(ctxt, (u16)cs, VCPU_SREG_CS);
> >> +        if (rc != X86EMUL_CONTINUE)
> >> +                return rc;
> >> +        rsp_increment(ctxt, ctxt->src.val);
> >> +        return X86EMUL_CONTINUE;
> >> +}
> >> +
> > Why not:
> > 
> > static int em_ret_far_imm(struct x86_emulate_ctxt *ctxt)
> > {
> > 	int rc;
> > 	rc = em_ret_far(struct x86_emulate_ctxt *ctxt);
> > 	if (rc != X86EMUL_CONTINUE)
> > 		return rc;
> > 	rsp_increment(ctxt, ctxt->src.val);
> > 	return X86EMUL_CONTINUE;
> > }
> > 
> > --
> > 			Gleb.
> 
> Yes, that does seem better. Ack.
> 
Somebody still needs to write a proper patch :) Can you do it please?

--
			Gleb.