Re: [PATCH v6 03/16] KVM: TDX: Pass KVM page level to tdh_mem_page_add() and tdh_mem_page_aug()

From: Isaku Yamahata
Date: Thu Nov 16 2023 - 19:23:39 EST


On Thu, Nov 16, 2023 at 04:18:28PM +0800,
Binbin Wu <binbin.wu@xxxxxxxxxxxxxxx> wrote:

> > diff --git a/arch/x86/kvm/vmx/tdx_ops.h b/arch/x86/kvm/vmx/tdx_ops.h
> > index e726102d3523..0f2df7198bde 100644
> > --- a/arch/x86/kvm/vmx/tdx_ops.h
> > +++ b/arch/x86/kvm/vmx/tdx_ops.h
> > @@ -63,6 +63,11 @@ static inline u64 tdx_seamcall(u64 op, u64 rcx, u64 rdx, u64 r8, u64 r9,
> > void pr_tdx_error(u64 op, u64 error_code, const struct tdx_module_args *out);
> > #endif
> > +static inline enum pg_level tdx_sept_level_to_pg_level(int tdx_level)
> > +{
> > + return tdx_level + 1;
> > +}
> > +
> > static inline void tdx_clflush_page(hpa_t addr, enum pg_level level)
> > {
> > clflush_cache_range(__va(addr), KVM_HPAGE_SIZE(level));
> > @@ -104,11 +109,11 @@ static inline u64 tdh_mng_addcx(hpa_t tdr, hpa_t addr)
> > return tdx_seamcall(TDH_MNG_ADDCX, addr, tdr, 0, 0, NULL);
> > }
> > -static inline u64 tdh_mem_page_add(hpa_t tdr, gpa_t gpa, hpa_t hpa, hpa_t source,
> > - struct tdx_module_args *out)
> > +static inline u64 tdh_mem_page_add(hpa_t tdr, gpa_t gpa, int level, hpa_t hpa,
> > + hpa_t source, struct tdx_module_args *out)
> > {
> > - tdx_clflush_page(hpa, PG_LEVEL_4K);
> > - return tdx_seamcall_sept(TDH_MEM_PAGE_ADD, gpa, tdr, hpa, source, out);
> > + tdx_clflush_page(hpa, tdx_sept_level_to_pg_level(level));
> > + return tdx_seamcall_sept(TDH_MEM_PAGE_ADD, gpa | level, tdr, hpa, source, out);
> > }
>
> For TDH_MEM_PAGE_ADD, only 4K page is supported, is this change necessary?
> Or maybe huge page can be supported by TDH_MEM_PAGE_ADD in the future?


No and no. Will drop the argument. Nice catch.
--
Isaku Yamahata <isaku.yamahata@xxxxxxxxxxxxxxx>