From patchwork Tue Dec 12 20:46:35 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sagi Shahar X-Patchwork-Id: 754138 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="d0LqSesu" Received: from mail-pj1-x104a.google.com (mail-pj1-x104a.google.com [IPv6:2607:f8b0:4864:20::104a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 360EA199E for ; Tue, 12 Dec 2023 12:47:37 -0800 (PST) Received: by mail-pj1-x104a.google.com with SMTP id 98e67ed59e1d1-28658658190so3803258a91.1 for ; Tue, 12 Dec 2023 12:47:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1702414056; x=1703018856; 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=OBiOJZf7KtnyH3BNNYJPAadRM1tNvWRCeEycOvMN+pU=; b=d0LqSesupPyoyeKwkexykEQMzR1KMSdHREVUqJ6oYwbbq+Y3TfS09l5bEprzHjUFA0 6vdbDzLnrPQTnmH6h3fuGmA61Ng9Ax99+NMemlNAJJ0QkF1z00u9MVv4cYkm5Cq/7iq5 LApkWGr/hT+l0ZDHSzoqdYaWeU7gejiWuJdk0MVz3Z0CeqDokXjGxwPoe34L+pm0rY26 Np5rpdYdiQvWTIAzNk4QMpCHZl3B//cIU940vx5/Ld+DndQeLB00DTzisyHrBJ/9LxLn ZagUSfLsTe13dlPNEnJxwcVHq+N5u3vuqxG4BqVdzYyuQ3CNjjdhYG3CpOG1iU2ZRO4z o3SQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702414056; x=1703018856; 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=OBiOJZf7KtnyH3BNNYJPAadRM1tNvWRCeEycOvMN+pU=; b=N6JNIclLJN5ksT7mr4bAxWwtXqzPK51P/lmqhECGNXiWqSP410tVDagWx9CfdSq6w7 FobFSFvAgSvxPl+R7Flvi588OkJ5BtTXo2vJFofZb9F/7pKd0an/dDlQS5Ll36GLNWr9 q9v4rVRzcI12qtdce/JfWq3f6OPTRctyWpXq2KJemsY7slNd6WiIFZ/yR+SGJSEni1YB HSGLLvan2nf/0tlRZVUkUsysYgvV/tsv0QDekBcSnbWToJEaiwgC1cpfK3otgdmDVCku 1P5O11p4aLbX3boRGH29uwNpdya3MkUfZkE79VMGiM31+86DpvQ7Z+87HmA9/moYxxa4 031w== X-Gm-Message-State: AOJu0Yz6sGW07AvXE9LkNh99mtIxDQK7QayP4fgXshTkI9h0lvzA6hjJ CtBW5ohaY9LIaaTYtEsuwfSuMmBngFrzz/Ow7sJM791f4x3jCmpsaksFKTddkUaiNgyrYOu6BNI l3cuu1WaYKLpJtKj8HelUu+syD9zPtxlmhN5sqzO7/0ijipWU8tlObLh5h+EhA63Wqrnyp5Q= X-Google-Smtp-Source: AGHT+IF9mFDmE+EjddG5s/SyOCpTwUm15KmEORbZmtsVTD+OTDrv2Qk/i5lTzBYVQ+p74U2xuSBWL1QG8w== X-Received: from sagi.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:241b]) (user=sagis job=sendgmr) by 2002:a17:902:cec5:b0:1d2:f388:6def with SMTP id d5-20020a170902cec500b001d2f3886defmr52709plg.10.1702414055001; Tue, 12 Dec 2023 12:47:35 -0800 (PST) Date: Tue, 12 Dec 2023 12:46:35 -0800 In-Reply-To: <20231212204647.2170650-1-sagis@google.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20231212204647.2170650-1-sagis@google.com> X-Mailer: git-send-email 2.43.0.472.g3155946c3a-goog Message-ID: <20231212204647.2170650-21-sagis@google.com> Subject: [RFC PATCH v5 20/29] KVM: selftests: TDX: Verify the behavior when host consumes a TD private memory From: Sagi Shahar To: linux-kselftest@vger.kernel.org, Ackerley Tng , Ryan Afranji , Erdem Aktas , Sagi Shahar , Isaku Yamahata Cc: Sean Christopherson , Paolo Bonzini , Shuah Khan , Peter Gonda , Haibo Xu , Chao Peng , Vishal Annapurve , Roger Wang , Vipin Sharma , jmattson@google.com, dmatlack@google.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org 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 Signed-off-by: Ackerley Tng --- .../selftests/kvm/x86_64/tdx_vm_tests.c | 85 +++++++++++++++++++ 1 file changed, 85 insertions(+) diff --git a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c index 6935604d768b..c977223ff871 100644 --- a/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c +++ b/tools/testing/selftests/kvm/x86_64/tdx_vm_tests.c @@ -1062,6 +1062,90 @@ void verify_td_cpuid_tdcall(void) printf("\t ... PASSED\n"); } +/* + * Shared variables between guest and host for host reading private mem test + */ +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 ret; + uint64_t placeholder = 0; + + /* Set value */ + *((uint32_t *) tdx_test_host_read_private_mem_addr) = 0xABCD; + + /* Exit so host can read value */ + ret = tdg_vp_vmcall_instruction_io( + TDX_HOST_READ_PRIVATE_MEM_PORT_TEST, 4, + TDG_VP_VMCALL_INSTRUCTION_IO_WRITE, &placeholder); + if (ret) + tdx_test_fatal(ret); + + /* Update guest_var's value and have host reread it. */ + *((uint32_t *) tdx_test_host_read_private_mem_addr) = 0xFEDC; + + tdx_test_success(); +} + +void verify_host_reading_private_mem(void) +{ + struct kvm_vm *vm; + struct kvm_vcpu *vcpu; + + vm_vaddr_t test_page; + uint64_t *host_virt; + uint64_t first_host_read; + uint64_t second_host_read; + + vm = td_create(); + td_initialize(vm, VM_MEM_SRC_ANONYMOUS, 0); + vcpu = td_vcpu_add(vm, 0, guest_host_read_priv_mem); + + test_page = 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 = addr_gva2hva(vm, test_page); + TEST_ASSERT(host_virt != NULL, + "Guest address not found in guest memory regions\n"); + + tdx_test_host_read_private_mem_addr = 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"); + + td_vcpu_run(vcpu); + TDX_TEST_CHECK_GUEST_FAILURE(vcpu); + TDX_TEST_ASSERT_IO(vcpu, TDX_HOST_READ_PRIVATE_MEM_PORT_TEST, + 4, TDG_VP_VMCALL_INSTRUCTION_IO_WRITE); + printf("\t ... Guest's variable contains 0xABCD\n"); + + /* Host reads guest's variable. */ + first_host_read = *host_virt; + printf("\t ... Host's read attempt value: %lu\n", first_host_read); + + /* Guest updates variable and host rereads it. */ + td_vcpu_run(vcpu); + TDX_TEST_CHECK_GUEST_FAILURE(vcpu); + printf("\t ... Guest's variable updated to 0xFEDC\n"); + + second_host_read = *host_virt; + printf("\t ... Host's second read attempt value: %lu\n", + second_host_read); + + TEST_ASSERT(first_host_read == 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) { setbuf(stdout, NULL); @@ -1084,6 +1168,7 @@ int main(int argc, char **argv) run_in_new_process(&verify_mmio_reads); run_in_new_process(&verify_mmio_writes); run_in_new_process(&verify_td_cpuid_tdcall); + run_in_new_process(&verify_host_reading_private_mem); return 0; }