Re: [PATCH v13 098/113] KVM: TDX: Handle TDX PV map_gpa hypercall

From: Vishal Annapurve
Date: Tue Apr 18 2023 - 15:09:28 EST


> +static int tdx_map_gpa(struct kvm_vcpu *vcpu)
> +{
> + struct kvm *kvm = vcpu->kvm;
> + gpa_t gpa = tdvmcall_a0_read(vcpu);
> + gpa_t size = tdvmcall_a1_read(vcpu);
> + gpa_t end = gpa + size;
> +
> + if (!IS_ALIGNED(gpa, PAGE_SIZE) || !IS_ALIGNED(size, PAGE_SIZE) ||
> + end < gpa ||
> + end > kvm_gfn_shared_mask(kvm) << (PAGE_SHIFT + 1) ||
> + kvm_is_private_gpa(kvm, gpa) != kvm_is_private_gpa(kvm, end)) {
> + tdvmcall_set_return_code(vcpu, TDG_VP_VMCALL_INVALID_OPERAND);
> + return 1;
> + }
> +
> + return tdx_vp_vmcall_to_user(vcpu);

This will result into exits to userspace for MMIO regions as well. Does it make
sense to only exit to userspace for guest physical memory regions backed by
memslots?

> +}
> +