From patchwork Thu Sep 16 18:15:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Upton X-Patchwork-Id: 12500037 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-23.5 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C15F4C433FE for ; Thu, 16 Sep 2021 18:56:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AB52560F11 for ; Thu, 16 Sep 2021 18:56:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343567AbhIPS6F (ORCPT ); Thu, 16 Sep 2021 14:58:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343534AbhIPS5b (ORCPT ); Thu, 16 Sep 2021 14:57:31 -0400 Received: from mail-qk1-x749.google.com (mail-qk1-x749.google.com [IPv6:2607:f8b0:4864:20::749]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60DDEC04A15C for ; Thu, 16 Sep 2021 11:16:01 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id t18-20020a05620a0b1200b003f8729fdd04so44903043qkg.5 for ; Thu, 16 Sep 2021 11:16:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=8hwcEJHqqbleK2q5f0fxT+gCTiuJIDnqJ/WMYEHLAVo=; b=asi7q4GVc4ugGoEOJPY7JkUr5Ekx5zAnLtsBgfljrtz1r2yP2SheAoo8avJtMz2gHV 5KKv13LRBvrhQy258V7nVJcsziRzYsUlnqTBxi41nowjyA5QP8kufy0zpL9NdA1EwR6R 6mf2cSimFD7S7EOx+Xw9EJoOncHRmdSTbYLn0DxB3BcYO/kRztd9bwnrhczufwGApTSy jGTcoXQF7x17dFB6Zx+PxZRqbCqBjmsEwTfnxNImoRK50t01+Rt+v/c7HMbLaEGJw4cR zTl4ANdeibSv5/4unBjx6j+yHVR2Lido9De+UPkHXUJ+YV3+D2aLHvg9x/nbCEuVcNfn lwNA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=8hwcEJHqqbleK2q5f0fxT+gCTiuJIDnqJ/WMYEHLAVo=; b=rRl+wAp/YdCVvQTDO/N40DeKhMSod3uUVLLYOva+iDBRvg4c5t1D+LDB9X2PNNxfNY DBx3mnv7NMkMim6ouKxB5vVUIDumvxdL/ElunI4r9gx/Sv798SJq5wMBjZlpafJYpkH1 SQ+5u5XSxqWfwTdxyLxjPlJq5MiVnMnGGia3F7u2UnimZlOowp4Vr3MFC50NM8y8MGat h6PKZzkHvDCcRjVDnNpIa4zFrsni+tALmbftV/Z9WA5EQkHikMQd/wb4pb+YgoUi8RDK QUqN/sE+kvIxWOmJftZtvg3vtCEg4i0etskVYhPWXkesd6jTVbTvYJ1e8wCz6i8dAEZE S1AQ== X-Gm-Message-State: AOAM530eKIXZofEAkCeThLY3tiRUY7SQg4D+u58+cXbG52WSKqjTDD66 9h8llQ9qQCn4ZL6BFLol7C4QlFfjtM0LiwJI2cMxnF1Y2nzXPOMpYQjhvf4vdDdiYsPKQt2sun0 gNtYCZ0P6L7bfNnnwJVu86LQo2zs+Dl4cv3H/aNqYhiUW+yAH/Sh/owx5Ng== X-Google-Smtp-Source: ABdhPJy3jL77qYtBUKKnxIe+VvWNRdA1nJDNgwdjh9SJ7OcSuPBR0J08eguS6Zh+JtzbrCSmFUH78KJSPPw= X-Received: from oupton.c.googlers.com ([fda3:e722:ac3:cc00:2b:ff92:c0a8:404]) (user=oupton job=sendgmr) by 2002:a05:6214:1271:: with SMTP id r17mr6872494qvv.48.1631816160428; Thu, 16 Sep 2021 11:16:00 -0700 (PDT) Date: Thu, 16 Sep 2021 18:15:48 +0000 In-Reply-To: <20210916181555.973085-1-oupton@google.com> Message-Id: <20210916181555.973085-3-oupton@google.com> Mime-Version: 1.0 References: <20210916181555.973085-1-oupton@google.com> X-Mailer: git-send-email 2.33.0.464.g1972c5931b-goog Subject: [PATCH v8 2/9] selftests: KVM: Add test for KVM_{GET,SET}_CLOCK From: Oliver Upton To: kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu Cc: Paolo Bonzini , Sean Christopherson , Marc Zyngier , Peter Shier , Jim Mattson , David Matlack , Ricardo Koller , Jing Zhang , Raghavendra Rao Anata , James Morse , Alexandru Elisei , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, Andrew Jones , Will Deacon , Catalin Marinas , Oliver Upton Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Add a selftest for the new KVM clock UAPI that was introduced. Ensure that the KVM clock is consistent between userspace and the guest, and that the difference in realtime will only ever cause the KVM clock to advance forward. Cc: Andrew Jones Signed-off-by: Oliver Upton --- tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../testing/selftests/kvm/include/kvm_util.h | 2 + .../selftests/kvm/x86_64/kvm_clock_test.c | 204 ++++++++++++++++++ 4 files changed, 208 insertions(+) create mode 100644 tools/testing/selftests/kvm/x86_64/kvm_clock_test.c diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 98053d3afbda..86a063d1cd3e 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -12,6 +12,7 @@ /x86_64/emulator_error_test /x86_64/get_cpuid_test /x86_64/get_msr_index_features +/x86_64/kvm_clock_test /x86_64/kvm_pv_test /x86_64/hyperv_clock /x86_64/hyperv_cpuid diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 5d05801ab816..1f969b0192f6 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -46,6 +46,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/get_cpuid_test TEST_GEN_PROGS_x86_64 += x86_64/hyperv_clock TEST_GEN_PROGS_x86_64 += x86_64/hyperv_cpuid TEST_GEN_PROGS_x86_64 += x86_64/hyperv_features +TEST_GEN_PROGS_x86_64 += x86_64/kvm_clock_test TEST_GEN_PROGS_x86_64 += x86_64/kvm_pv_test TEST_GEN_PROGS_x86_64 += x86_64/mmio_warning_test TEST_GEN_PROGS_x86_64 += x86_64/mmu_role_test diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index 010b59b13917..a8ac5d52e17b 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -19,6 +19,8 @@ #define KVM_DEV_PATH "/dev/kvm" #define KVM_MAX_VCPUS 512 +#define NSEC_PER_SEC 1000000000L + /* * Callers of kvm_util only have an incomplete/opaque description of the * structure kvm_util is using to maintain the state of a VM. diff --git a/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c b/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c new file mode 100644 index 000000000000..e0dcc27ae9f1 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/kvm_clock_test.c @@ -0,0 +1,204 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021, Google LLC. + * + * Tests for adjusting the KVM clock from userspace + */ +#include +#include +#include +#include +#include +#include +#include + +#include "test_util.h" +#include "kvm_util.h" +#include "processor.h" + +#define VCPU_ID 0 + +struct test_case { + uint64_t kvmclock_base; + int64_t realtime_offset; +}; + +static struct test_case test_cases[] = { + { .kvmclock_base = 0 }, + { .kvmclock_base = 180 * NSEC_PER_SEC }, + { .kvmclock_base = 0, .realtime_offset = -180 * NSEC_PER_SEC }, + { .kvmclock_base = 0, .realtime_offset = 180 * NSEC_PER_SEC }, +}; + +#define GUEST_SYNC_CLOCK(__stage, __val) \ + GUEST_SYNC_ARGS(__stage, __val, 0, 0, 0) + +static void guest_main(vm_paddr_t pvti_pa, struct pvclock_vcpu_time_info *pvti) +{ + int i; + + wrmsr(MSR_KVM_SYSTEM_TIME_NEW, pvti_pa | KVM_MSR_ENABLED); + for (i = 0; i < ARRAY_SIZE(test_cases); i++) + GUEST_SYNC_CLOCK(i, __pvclock_read_cycles(pvti, rdtsc())); +} + +#define EXPECTED_FLAGS (KVM_CLOCK_REALTIME | KVM_CLOCK_HOST_TSC) + +static inline void assert_flags(struct kvm_clock_data *data) +{ + TEST_ASSERT((data->flags & EXPECTED_FLAGS) == EXPECTED_FLAGS, + "unexpected clock data flags: %x (want set: %x)", + data->flags, EXPECTED_FLAGS); +} + +static void handle_sync(struct ucall *uc, struct kvm_clock_data *start, + struct kvm_clock_data *end) +{ + uint64_t obs, exp_lo, exp_hi; + + obs = uc->args[2]; + exp_lo = start->clock; + exp_hi = end->clock; + + assert_flags(start); + assert_flags(end); + + TEST_ASSERT(exp_lo <= obs && obs <= exp_hi, + "unexpected kvm-clock value: %"PRIu64" expected range: [%"PRIu64", %"PRIu64"]", + obs, exp_lo, exp_hi); + + pr_info("kvm-clock value: %"PRIu64" expected range [%"PRIu64", %"PRIu64"]\n", + obs, exp_lo, exp_hi); +} + +static void handle_abort(struct ucall *uc) +{ + TEST_FAIL("%s at %s:%ld", (const char *)uc->args[0], + __FILE__, uc->args[1]); +} + +static void setup_clock(struct kvm_vm *vm, struct test_case *test_case) +{ + struct kvm_clock_data data; + + memset(&data, 0, sizeof(data)); + + data.clock = test_case->kvmclock_base; + if (test_case->realtime_offset) { + struct timespec ts; + int r; + + data.flags |= KVM_CLOCK_REALTIME; + do { + r = clock_gettime(CLOCK_REALTIME, &ts); + if (!r) + break; + } while (errno == EINTR); + + TEST_ASSERT(!r, "clock_gettime() failed: %d\n", r); + + data.realtime = ts.tv_sec * NSEC_PER_SEC; + data.realtime += ts.tv_nsec; + data.realtime += test_case->realtime_offset; + } + + vm_ioctl(vm, KVM_SET_CLOCK, &data); +} + +static void enter_guest(struct kvm_vm *vm) +{ + struct kvm_clock_data start, end; + struct kvm_run *run; + struct ucall uc; + int i, r; + + run = vcpu_state(vm, VCPU_ID); + + for (i = 0; i < ARRAY_SIZE(test_cases); i++) { + setup_clock(vm, &test_cases[i]); + + vm_ioctl(vm, KVM_GET_CLOCK, &start); + + r = _vcpu_run(vm, VCPU_ID); + vm_ioctl(vm, KVM_GET_CLOCK, &end); + + TEST_ASSERT(!r, "vcpu_run failed: %d\n", r); + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "unexpected exit reason: %u (%s)", + run->exit_reason, exit_reason_str(run->exit_reason)); + + switch (get_ucall(vm, VCPU_ID, &uc)) { + case UCALL_SYNC: + handle_sync(&uc, &start, &end); + break; + case UCALL_ABORT: + handle_abort(&uc); + return; + default: + TEST_ASSERT(0, "unhandled ucall: %ld\n", + get_ucall(vm, VCPU_ID, &uc)); + } + } +} + +#define CLOCKSOURCE_PATH "/sys/devices/system/clocksource/clocksource0/current_clocksource" + +static void check_clocksource(void) +{ + char *clk_name; + struct stat st; + FILE *fp; + + fp = fopen(CLOCKSOURCE_PATH, "r"); + if (!fp) { + pr_info("failed to open clocksource file: %d; assuming TSC.\n", + errno); + return; + } + + if (fstat(fileno(fp), &st)) { + pr_info("failed to stat clocksource file: %d; assuming TSC.\n", + errno); + goto out; + } + + clk_name = malloc(st.st_size); + TEST_ASSERT(clk_name, "failed to allocate buffer to read file\n"); + + if (!fgets(clk_name, st.st_size, fp)) { + pr_info("failed to read clocksource file: %d; assuming TSC.\n", + ferror(fp)); + goto out; + } + + TEST_ASSERT(!strncmp(clk_name, "tsc\n", st.st_size), + "clocksource not supported: %s", clk_name); +out: + fclose(fp); +} + +int main(void) +{ + vm_vaddr_t pvti_gva; + vm_paddr_t pvti_gpa; + struct kvm_vm *vm; + int flags; + + flags = kvm_check_cap(KVM_CAP_ADJUST_CLOCK); + if (!(flags & KVM_CLOCK_REALTIME)) { + print_skip("KVM_CLOCK_REALTIME not supported; flags: %x", + flags); + exit(KSFT_SKIP); + } + + check_clocksource(); + + vm = vm_create_default(VCPU_ID, 0, guest_main); + + pvti_gva = vm_vaddr_alloc(vm, getpagesize(), 0x10000); + pvti_gpa = addr_gva2gpa(vm, pvti_gva); + vcpu_args_set(vm, VCPU_ID, 2, pvti_gpa, pvti_gva); + + enter_guest(vm); + kvm_vm_free(vm); +}