>
> +static void snp_handle_guest_request(struct vcpu_svm *svm, struct ghcb *ghcb,
> + gpa_t req_gpa, gpa_t resp_gpa)
> +{
> + struct sev_data_snp_guest_request data = {};
> + struct kvm_vcpu *vcpu = &svm->vcpu;
> + struct kvm *kvm = vcpu->kvm;
> + kvm_pfn_t req_pfn, resp_pfn;
> + struct kvm_sev_info *sev;
> + int rc, err = 0;
> +
> + if (!sev_snp_guest(vcpu->kvm)) {
> + rc = -ENODEV;
> + goto e_fail;
> + }
> +
> + sev = &to_kvm_svm(kvm)->sev_info;
> +
> + if (!__ratelimit(&sev->snp_guest_msg_rs)) {
> + pr_info_ratelimited("svm: too many guest message requests\n");
> + rc = -EAGAIN;
> + goto e_fail;
> + }
> +
> + if (!IS_ALIGNED(req_gpa, PAGE_SIZE) || !IS_ALIGNED(resp_gpa, PAGE_SIZE)) {
> + pr_err("svm: guest request (%#llx) or response (%#llx) is not page aligned\n",
> + req_gpa, resp_gpa);
> + goto e_term;
> + }
> +
> + req_pfn = gfn_to_pfn(kvm, gpa_to_gfn(req_gpa));
> + if (is_error_noslot_pfn(req_pfn)) {
> + pr_err("svm: guest request invalid gpa=%#llx\n", req_gpa);
> + goto e_term;
> + }
> +
> + resp_pfn = gfn_to_pfn(kvm, gpa_to_gfn(resp_gpa));
> + if (is_error_noslot_pfn(resp_pfn)) {
> + pr_err("svm: guest response invalid gpa=%#llx\n", resp_gpa);
> + goto e_term;
> + }
> +
> + data.gctx_paddr = __psp_pa(sev->snp_context);
> + data.req_paddr = __sme_set(req_pfn << PAGE_SHIFT);
> + data.res_paddr = __psp_pa(sev->snp_resp_page);
> +
> + mutex_lock(&kvm->lock);
> +
> + rc = sev_issue_cmd(kvm, SEV_CMD_SNP_GUEST_REQUEST, &data, &err);
> + if (rc) {
> + mutex_unlock(&kvm->lock);
> +
> + /* If we have a firmware error code then use it. */
> + if (err)
> + rc = err;
> +
> + goto e_fail;
> + }
> +
> + /* Copy the response after the firmware returns success. */
> + rc = kvm_write_guest(kvm, resp_gpa, sev->snp_resp_page, PAGE_SIZE);
> +
> + mutex_unlock(&kvm->lock);
> +
> +e_fail:
> + ghcb_set_sw_exit_info_2(ghcb, rc);
> + return;
> +
> +e_term:
> + ghcb_set_sw_exit_info_1(ghcb, 1);
> + ghcb_set_sw_exit_info_2(ghcb,
> + X86_TRAP_GP |
> + SVM_EVTINJ_TYPE_EXEPT |
> + SVM_EVTINJ_VALID);
> +}
I am probably missing something in the spec but I don't see any
references to #GP in the '4.1.7 SNP Guest Request' section. Why is
this different from e_fail?
