Re: [PATCH] When switching to a vm8086 task, load segments as 16-bit

[Anthony Liguori <aliguori@us.ibm.com>]

Avi Kivity wrote:
> On 08/11/2009 04:00 AM, Anthony Liguori wrote:
>
> kvm_load_segment_descriptor() can already load plain segments:
>
>     if (!(vcpu->arch.cr0 & X86_CR0_PE))
>         return kvm_load_realmode_segment(vcpu, selector, seg);
>
> so we can simplify the patch a bit by extending the check.

I went down that road but you need to check the to-be-switched-into tss, 
which isn't available directly from vcpu so we would have to either pass 
the tss as a parameter to the function or at least a flag indicating 
that we're going into vm8086 mode.

There are other callers of kvm_load_segment_descriptor that would need 
updating and it already takes a few extra parameters.  That's why I went 
down this road.

Happy to change though if you'd prefer a different approach.

-- 
Regards,

Anthony Liguori