On Wed, May 01, 2024 at 03:51:52AM -0500,
Michael Roth <michael.roth@xxxxxxx> wrote:
...
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index c6c5018376be..87265b73906a 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1816,6 +1816,7 @@ struct kvm_x86_ops {
> void *(*alloc_apic_backing_page)(struct kvm_vcpu *vcpu);
> int (*gmem_prepare)(struct kvm *kvm, kvm_pfn_t pfn, gfn_t gfn, int max_order);
> void (*gmem_invalidate)(kvm_pfn_t start, kvm_pfn_t end);
> + int (*private_max_mapping_level)(struct kvm *kvm, kvm_pfn_t pfn);
Explicit private prefix is nice.
> };
>
> struct kvm_x86_nested_ops {
> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
> index 510eb1117012..0d556da052f6 100644
> --- a/arch/x86/kvm/mmu/mmu.c
> +++ b/arch/x86/kvm/mmu/mmu.c
> @@ -4271,6 +4271,20 @@ static inline u8 kvm_max_level_for_order(int order)
> return PG_LEVEL_4K;
> }
>
> +static u8 kvm_max_private_mapping_level(struct kvm *kvm, kvm_pfn_t pfn,
> + u8 max_level, int gmem_order)
> +{
> + if (max_level == PG_LEVEL_4K)
> + return PG_LEVEL_4K;
> +
> + max_level = min(kvm_max_level_for_order(gmem_order), max_level);
> + if (max_level == PG_LEVEL_4K)
> + return PG_LEVEL_4K;
> +
> + return min(max_level,
> + static_call(kvm_x86_private_max_mapping_level)(kvm, pfn));
If we don't implement this hook, OPTIONAL_RET0 causes always PG_LEVEL_NONE.
Anyway when TDX implements the hook, we can remove OPTIONAL_RET0.
This hook works for TDX by "return PG_LEVEL_4K;".
Reviewed-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
