From nobody Sun Oct 5 07:26:09 2025 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 375A324886C for ; Thu, 7 Aug 2025 20:17:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754597832; cv=none; b=iQf+soRNV8E6JTui8mdP/PmZ4JWr8Q79/nNOs6viuRnbC3swWCYdYdUv37QTg1K1MPN2YgtaHJP2xswINfmRiusYSp++MOpsN4mjFIe1b4l4SDx+tWoIbQ8pIihid2oF5tneLmpUpFWpiluR3ecWRnv+Q6aeXVTGgqodeLOJdPk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754597832; c=relaxed/simple; bh=RXVJT3xKKpDFgdngx9y4dlRBL6JQNyl8/5ZSR2/B66Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=sOqB2Xfic1StUz3YZm805WpuhLgp5wF7YQ/sUtVLQTNEVRvGC0Z9WSj7wuaovCqAZsOzuggiqRMhbQ3+9RQb46spD9q/pip+hpns5wxkVjusObNKQCUeY+GbG+an/BksqkNhcTDef5RJr1KTphENkXkteK3/D7hCbDg+i+uTVvI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--sagis.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=U35JFMmW; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--sagis.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="U35JFMmW" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-242abac2cb4so18204185ad.0 for ; Thu, 07 Aug 2025 13:17:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1754597830; x=1755202630; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=+3/DP/toZqy9fmiCiLsTNtC3sfq1PRsX7V9GLb3O0mQ=; b=U35JFMmWGwUcgwDR+NKWxUhJKmVhg30H8aZc9PS4fSQ5E151HpcNUYV4pRFDxUtn7N K7x/cqi8pBi0HMhjj7THDfQM89CR9Jhkx/CDLGzN0dbPXT49/iD+WQDv0aMi2l4Xra7/ RMhNmWSwxRFo8MT0xTRa7oajKyM90ARR2gICPmcazZ2k+e/QApEyGCVOd384Y+3ozjoW 5hsStYmu3vxTNIB420Bu4IJWNeI6w6zxUJiuE92JocQOywtncQnISPNOLktbSgPNiv2r ujhXCNLUbDPgegFFN4pwYysdqBZQeTHkxWUz+eIbmrDfEwhgUSYZXglnrmDMZswZovoj 9r5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754597830; x=1755202630; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=+3/DP/toZqy9fmiCiLsTNtC3sfq1PRsX7V9GLb3O0mQ=; b=QO0oZnF5YtQmhJmOToQEhqTEhdnga/cp7z+sMBTR+8kIuA6IIllefJabBjEFkJrN9D SwKrk5PrndW3+DWQizcXUVimRuQqFf4g7sKG/R4wGOlSDxEdQ/brbooyj97jbH1JZ36u z/sbKAXtzCxWp0fGdHdDhnBunuUQjDMrNYW3O2qlkzyV3ANTaKHeWb0IchdB9N5S21ON kayCUZRejDnTpyLkjoS+/vrOrMetAu33KPfCprHiAd7DfzCb8aO3N3r6DhbXIXNmyqZz yHZcXE0VWiLFdwCpwwXUggClMla9t8qcDKJrMzQTOpTidb4HQ7CpWVkjWSipUVI0JtXU RAsQ== X-Gm-Message-State: AOJu0YwnJtpmro56XVkx0gdmDI2S1qpFPB5ULuTISmAZ9DvneRD7kYse 346+flHHEWaWd6oxxiJkm0PV1LIMaeK8t4ryaT8x2i5Sj+Cx9WtDhbBJFifeujGj90vKilRhVSF oTg== X-Google-Smtp-Source: AGHT+IFJRnQ83ttz5IZxiNzcWF87OdqmEuYc3wMh19wWZE0+e7hLOUX6rDQmIqYB8sf4aztyJmmEccl9/A== X-Received: from pjpy17.prod.google.com ([2002:a17:90a:a411:b0:321:370d:cae5]) (user=sagis job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:8cd:b0:21f:4649:fd49 with SMTP id d9443c01a7336-242c222b0abmr4455255ad.49.1754597829703; Thu, 07 Aug 2025 13:17:09 -0700 (PDT) Date: Thu, 7 Aug 2025 13:16:17 -0700 In-Reply-To: <20250807201628.1185915-1-sagis@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250807201628.1185915-1-sagis@google.com> X-Mailer: git-send-email 2.51.0.rc0.155.g4a0f42376b-goog Message-ID: <20250807201628.1185915-22-sagis@google.com> Subject: [PATCH v8 21/30] KVM: selftests: TDX: Verify the behavior when host consumes a TD private memory From: Sagi Shahar To: linux-kselftest@vger.kernel.org, Paolo Bonzini , Shuah Khan , Sean Christopherson , Ackerley Tng , Ryan Afranji , Andrew Jones , Isaku Yamahata , Erdem Aktas , Rick Edgecombe , Sagi Shahar , Roger Wang , Binbin Wu , Oliver Upton , "Pratik R. Sampat" , Reinette Chatre , Ira Weiny Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Ryan Afranji The test checks that host can only read fixed values when trying to access the guest's private memory. Signed-off-by: Ryan Afranji Signed-off-by: Sagi Shahar --- tools/testing/selftests/kvm/x86/tdx_vm_test.c | 83 ++++++++++++++++++- 1 file changed, 82 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/kvm/x86/tdx_vm_test.c b/tools/testing/= selftests/kvm/x86/tdx_vm_test.c index 2f75f12d2a44..b6ef0348746c 100644 --- a/tools/testing/selftests/kvm/x86/tdx_vm_test.c +++ b/tools/testing/selftests/kvm/x86/tdx_vm_test.c @@ -959,6 +959,85 @@ void verify_td_cpuid_tdcall(void) printf("\t ... PASSED\n"); } =20 +/* + * Shared variables between guest and host for host reading private mem te= st + */ +static uint64_t tdx_test_host_read_private_mem_addr; +#define TDX_HOST_READ_PRIVATE_MEM_PORT_TEST 0x53 + +void guest_host_read_priv_mem(void) +{ + uint64_t placeholder =3D 0; + uint64_t ret; + + /* Set value */ + *((uint32_t *)tdx_test_host_read_private_mem_addr) =3D 0xABCD; + + /* Exit so host can read value */ + ret =3D tdg_vp_vmcall_instruction_io(TDX_HOST_READ_PRIVATE_MEM_PORT_TEST, + 4, PORT_WRITE, &placeholder); + tdx_assert_error(ret); + + /* Update guest_var's value and have host reread it. */ + *((uint32_t *)tdx_test_host_read_private_mem_addr) =3D 0xFEDC; + + tdx_test_success(); +} + +void verify_host_reading_private_mem(void) +{ + uint64_t second_host_read; + uint64_t first_host_read; + struct kvm_vcpu *vcpu; + vm_vaddr_t test_page; + uint64_t *host_virt; + struct kvm_vm *vm; + + vm =3D td_create(); + td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0); + vcpu =3D td_vcpu_add(vm, 0, guest_host_read_priv_mem); + + test_page =3D vm_vaddr_alloc_page(vm); + TEST_ASSERT(test_page < BIT_ULL(32), + "Test address should fit in 32 bits so it can be sent to the guest"); + + host_virt =3D addr_gva2hva(vm, test_page); + TEST_ASSERT(host_virt, + "Guest address not found in guest memory regions\n"); + + tdx_test_host_read_private_mem_addr =3D test_page; + sync_global_to_guest(vm, tdx_test_host_read_private_mem_addr); + + td_finalize(vm); + + printf("Verifying host's behavior when reading TD private memory:\n"); + + tdx_run(vcpu); + tdx_test_assert_io(vcpu, TDX_HOST_READ_PRIVATE_MEM_PORT_TEST, + 4, PORT_WRITE); + printf("\t ... Guest's variable contains 0xABCD\n"); + + /* Host reads guest's variable. */ + first_host_read =3D *host_virt; + printf("\t ... Host's read attempt value: %lu\n", first_host_read); + + /* Guest updates variable and host rereads it. */ + tdx_run(vcpu); + printf("\t ... Guest's variable updated to 0xFEDC\n"); + + second_host_read =3D *host_virt; + printf("\t ... Host's second read attempt value: %lu\n", + second_host_read); + + TEST_ASSERT(first_host_read =3D=3D second_host_read, + "Host did not read a fixed pattern\n"); + + printf("\t ... Fixed pattern was returned to the host\n"); + + kvm_vm_free(vm); + printf("\t ... PASSED\n"); +} + int main(int argc, char **argv) { ksft_print_header(); @@ -966,7 +1045,7 @@ int main(int argc, char **argv) if (!is_tdx_enabled()) ksft_exit_skip("TDX is not supported by the KVM. Exiting.\n"); =20 - ksft_set_plan(13); + ksft_set_plan(14); ksft_test_result(!run_in_new_process(&verify_td_lifecycle), "verify_td_lifecycle\n"); ksft_test_result(!run_in_new_process(&verify_report_fatal_error), @@ -993,6 +1072,8 @@ int main(int argc, char **argv) "verify_mmio_writes\n"); ksft_test_result(!run_in_new_process(&verify_td_cpuid_tdcall), "verify_td_cpuid_tdcall\n"); + ksft_test_result(!run_in_new_process(&verify_host_reading_private_mem), + "verify_host_reading_private_mem\n"); =20 ksft_finished(); return 0; --=20 2.51.0.rc0.155.g4a0f42376b-goog