From patchwork Fri Mar 18 10:46:44 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vasant Karasulli X-Patchwork-Id: 12785164 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33561C433F5 for ; Fri, 18 Mar 2022 10:47:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235194AbiCRKtM (ORCPT ); Fri, 18 Mar 2022 06:49:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235468AbiCRKsJ (ORCPT ); Fri, 18 Mar 2022 06:48:09 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 27A622C8B5A; Fri, 18 Mar 2022 03:46:51 -0700 (PDT) Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id CD7F921101; Fri, 18 Mar 2022 10:46:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1647600409; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fuOUCCwghJ7wAWelhl+tiI6onW5cn+IqhnW6uIi6Dq4=; b=C+hfIYgu94CeoIfjOi9Ct0NepPTqyLUa3/q+mFVbijintk/qt+7qqLhR8nhc1wG9a0AcA4 M8xym/9E+cO7UnUcZR8fs4b5Pl990OF8QTtUU5XgFDQHx6RwPhXTm8LCZ5NbdrKuMbgJ5H MMkD18RrTqN6AWIoxe6ude379O1qHWg= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1647600409; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fuOUCCwghJ7wAWelhl+tiI6onW5cn+IqhnW6uIi6Dq4=; b=ifb9oLjfvuBZDSLNTT4Ik2eSQp4U4dbLGVw+LmKIG8Varu0UpdVhZc9fAKADN263n8PA7f RB0QhFAnYh2TmbAw== Received: from vasant-suse.suse.de (unknown [10.163.24.178]) by relay2.suse.de (Postfix) with ESMTP id 8B31BA3B81; Fri, 18 Mar 2022 10:46:49 +0000 (UTC) From: Vasant Karasulli To: linux-kernel@vger.kernel.org, jroedel@suse.de, kvm@vger.kernel.org Cc: bp@alien8.de, x86@kernel.org, thomas.lendacky@amd.com, varad.gautam@suse.com, Vasant Karasulli Subject: [PATCH v6 2/4] x86/tests: Add tests for AMD SEV-ES #VC handling Date: Fri, 18 Mar 2022 11:46:44 +0100 Message-Id: <20220318104646.8313-3-vkarasulli@suse.de> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220318104646.8313-1-vkarasulli@suse.de> References: <20220318104646.8313-1-vkarasulli@suse.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add KUnit based tests to validate Linux's VC handling for instructions cpuid and wbinvd. These tests: 1. install a kretprobe on the #VC handler (sev_es_ghcb_hv_call, to access GHCB before/after the resulting VMGEXIT). 2. trigger an NAE by executing either cpuid or wbinvd. 3. check that the kretprobe was hit with the right exit_code available in GHCB. Signed-off-by: Vasant Karasulli --- arch/x86/tests/Makefile | 2 + arch/x86/tests/sev-test-vc.c | 114 +++++++++++++++++++++++++++++++++++ 2 files changed, 116 insertions(+) create mode 100644 arch/x86/tests/sev-test-vc.c -- 2.32.0 diff --git a/arch/x86/tests/Makefile b/arch/x86/tests/Makefile index f66554cd5c45..4beca64bd2aa 100644 --- a/arch/x86/tests/Makefile +++ b/arch/x86/tests/Makefile @@ -1 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_AMD_SEV_TEST_VC) += sev-test-vc.o diff --git a/arch/x86/tests/sev-test-vc.c b/arch/x86/tests/sev-test-vc.c new file mode 100644 index 000000000000..9d415b9708dc --- /dev/null +++ b/arch/x86/tests/sev-test-vc.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 SUSE + * + * Author: Varad Gautam + */ + +#include +#include +#include +#include +#include + +static struct kretprobe hv_call_krp; + +static int hv_call_krp_entry(struct kretprobe_instance *krpi, + struct pt_regs *regs) +{ + unsigned long ghcb_vaddr = regs_get_kernel_argument(regs, 0); + *((unsigned long *) krpi->data) = ghcb_vaddr; + + return 0; +} + +static int hv_call_krp_ret(struct kretprobe_instance *krpi, + struct pt_regs *regs) +{ + unsigned long ghcb_vaddr = *((unsigned long *) krpi->data); + struct ghcb *ghcb = (struct ghcb *) ghcb_vaddr; + struct kunit *test = current->kunit_test; + + if (test && strstr(test->name, "sev_es_") && test->priv) + *((u64 *)test->priv) = ghcb->save.sw_exit_code; + + return 0; +} + +int sev_es_test_vc_init(struct kunit *test) +{ + int ret; + + if (!cc_platform_has(CC_ATTR_GUEST_STATE_ENCRYPT)) { + kunit_info(test, "Not a SEV-ES guest. Skipping."); + ret = -EINVAL; + goto out; + } + + memset(&hv_call_krp, 0, sizeof(hv_call_krp)); + hv_call_krp.entry_handler = hv_call_krp_entry; + hv_call_krp.handler = hv_call_krp_ret; + hv_call_krp.maxactive = 100; + hv_call_krp.data_size = sizeof(unsigned long); + hv_call_krp.kp.symbol_name = "sev_es_ghcb_hv_call"; + hv_call_krp.kp.addr = 0; + + ret = register_kretprobe(&hv_call_krp); + if (ret) { + kunit_info(test, "Could not register kretprobe. Skipping."); + goto out; + } + + test->priv = kunit_kzalloc(test, sizeof(u64), GFP_KERNEL); + if (!test->priv) { + ret = -ENOMEM; + kunit_info(test, "Could not allocate. Skipping."); + goto out; + } + +out: + return ret; +} + +void sev_es_test_vc_exit(struct kunit *test) +{ + if (test->priv) + kunit_kfree(test, test->priv); + + if (hv_call_krp.kp.addr) + unregister_kretprobe(&hv_call_krp); +} + +#define check_op(kt, ec, op) \ +do { \ + struct kunit *t = (struct kunit *) kt; \ + op; \ + KUNIT_EXPECT_EQ(t, (typeof(ec)) ec, \ + *((typeof(ec) *)(t->priv))); \ +} while (0) + +static void sev_es_nae_cpuid(struct kunit *test) +{ + unsigned int cpuid_fn = 0x8000001f; + + check_op(test, SVM_EXIT_CPUID, native_cpuid_eax(cpuid_fn)); +} + +static void sev_es_nae_wbinvd(struct kunit *test) +{ + check_op(test, SVM_EXIT_WBINVD, wbinvd()); +} + +static struct kunit_case sev_es_vc_testcases[] = { + KUNIT_CASE(sev_es_nae_cpuid), + KUNIT_CASE(sev_es_nae_wbinvd), + {} +}; + +static struct kunit_suite sev_es_vc_test_suite = { + .name = "sev_es_test_vc", + .init = sev_es_test_vc_init, + .exit = sev_es_test_vc_exit, + .test_cases = sev_es_vc_testcases, +}; +kunit_test_suite(sev_es_vc_test_suite);