Re: [Qemu-devel] i386: EFER vs 32-bit CPU

[Paolo Bonzini]

On 29/05/19 13:30, Dr. David Alan Gilbert wrote:
>> Should we add a section for i386, which duplicates efer, or just version_id 
>> of the main VMSD should
>> be updated?
> 
> You could do:
> 
> #ifdef TARGET_X86_64
>         VMSTATE_UINT64(env.efer, X86CPU),
>         VMSTATE_UINT64(env.star, X86CPU),
> ...
> 
> to become:
> 
>         VMSTATE_UINT64_TEST(env.efer, X86CPU, efer_needed)
> #ifdef TARGET_X86_64
>         VMSTATE_UINT64(env.star, X86CPU),
> 
> 
> and then make efer_needed a function that returns true if
> TARGET_X86_64 or it's a new machine type that knows about whatever
> you're going to do with it.

I prefer adding a subsection for 32-bit, so that EFER is saved/restored
if nonzero.

Paolo