Re: [PATCH v2 5/6] KVM: x86: Track available/dirty register masks as "unsigned long" values

[Xiaoyao Li]

On 4/15/2026 7:29 PM, Xiaoyao Li wrote:
> > Note that updating only the "available" masks is wrong, as TDX needs 
> > to marshall
> > written registers back to their correct location.
>
> In what case it needs to marshall written registers back? Can you 
> elaborate?

Sorry that I asked a silly question. I mistakenly thought TDVMCALL for 
instructions (like, CPUID, RDMSR, WRMSR) use the same output register as 
the x86 instructions. After checking the TDX GHCI, obviously I'm wrong.

But I don't understand what's is wrong regarding "updating only the 
"available" masks". Or what is missing for "marshall written registers 
back to their correct location"?