Commit 20d91372 authored by Xiaoyao Li's avatar Xiaoyao Li Committed by Paolo Bonzini
Browse files

KVM: x86/mmu: Taking guest pa into consideration when calculate tdp level 



For TDX, the maxpa (CPUID.0x80000008.EAX[7:0]) is fixed as native and
the max_gpa (CPUID.0x80000008.EAX[23:16]) is configurable and used
to configure the EPT level and GPAW.

Use max_gpa to determine the TDP level.

Signed-off-by: default avatarXiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: default avatarRick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 488808e6

arch/x86/kvm/cpuid.c

+14 −0
Original line number Diff line number Diff line
@@ -463,6 +463,20 @@ int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu) 
	return 36;

}



int cpuid_query_maxguestphyaddr(struct kvm_vcpu *vcpu)

{

	struct kvm_cpuid_entry2 *best;



	best = kvm_find_cpuid_entry(vcpu, 0x80000000);

	if (!best || best->eax < 0x80000008)

		goto not_found;

	best = kvm_find_cpuid_entry(vcpu, 0x80000008);

	if (best)

		return (best->eax >> 16) & 0xff;

not_found:

	return 0;

}



/*

 * This "raw" version returns the reserved GPA bits without any adjustments for

 * encryption technologies that usurp bits.  The raw mask should be used if and

arch/x86/kvm/cpuid.h

+1 −0
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ void __init kvm_init_xstate_sizes(void); 
u32 xstate_required_size(u64 xstate_bv, bool compacted);



int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu);

int cpuid_query_maxguestphyaddr(struct kvm_vcpu *vcpu);

u64 kvm_vcpu_reserved_gpa_bits_raw(struct kvm_vcpu *vcpu);



static inline int cpuid_maxphyaddr(struct kvm_vcpu *vcpu)

arch/x86/kvm/mmu/mmu.c

+8 −1
Original line number Diff line number Diff line
@@ -5416,12 +5416,19 @@ void __kvm_mmu_refresh_passthrough_bits(struct kvm_vcpu *vcpu, 


static inline int kvm_mmu_get_tdp_level(struct kvm_vcpu *vcpu)

{

	int maxpa;



	if (vcpu->kvm->arch.vm_type == KVM_X86_TDX_VM)

		maxpa = cpuid_query_maxguestphyaddr(vcpu);

	else

		maxpa = cpuid_maxphyaddr(vcpu);



	/* tdp_root_level is architecture forced level, use it if nonzero */

	if (tdp_root_level)

		return tdp_root_level;



	/* Use 5-level TDP if and only if it's useful/necessary. */

	if (max_tdp_level == 5 && cpuid_maxphyaddr(vcpu) <= 48)

	if (max_tdp_level == 5 && maxpa <= 48)

		return 4;



	return max_tdp_level;