Re: [PATCH v19 039/130] KVM: TDX: initialize VM with TDX specific parameters

From: Isaku Yamahata
Date: Fri Mar 22 2024 - 21:22:36 EST


On Fri, Mar 22, 2024 at 11:20:01AM +0000,
"Huang, Kai" <kai.huang@xxxxxxxxx> wrote:

> On Mon, 2024-02-26 at 00:25 -0800, isaku.yamahata@xxxxxxxxx wrote:
> > +struct kvm_tdx_init_vm {
> > + __u64 attributes;
> > + __u64 mrconfigid[6]; /* sha384 digest */
> > + __u64 mrowner[6]; /* sha384 digest */
> > + __u64 mrownerconfig[6]; /* sha384 digest */
> > + /*
> > + * For future extensibility to make sizeof(struct kvm_tdx_init_vm) = 8KB.
> > + * This should be enough given sizeof(TD_PARAMS) = 1024.
> > + * 8KB was chosen given because
> > + * sizeof(struct kvm_cpuid_entry2) * KVM_MAX_CPUID_ENTRIES(=256) = 8KB.
> > + */
> > + __u64 reserved[1004];
>
> This is insane.
>
> You said you want to reserve 8K for CPUID entries, but how can these 1004 * 8
> bytes be used for CPUID entries since ...

I tried to overestimate it. It's too much, how about to make it
1024, reserved[109]?
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>