From mboxrd@z Thu Jan 1 00:00:00 1970 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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=ham 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 A7889C433DF for ; Tue, 19 May 2020 22:23:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75566206C3 for ; Tue, 19 May 2020 22:23:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="INoq135M" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728033AbgESWW7 (ORCPT ); Tue, 19 May 2020 18:22:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46502 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727097AbgESWW6 (ORCPT ); Tue, 19 May 2020 18:22:58 -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 5CC33C08C5C0 for ; Tue, 19 May 2020 15:22:58 -0700 (PDT) Received: by mail-qk1-x749.google.com with SMTP id d19so1598831qkj.21 for ; Tue, 19 May 2020 15:22:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=qbjnIgYBJ3XppSXgQQQYeUiA93XhGIz1VXZs5463P7w=; b=INoq135MwddeHyFBkmiondf71do3Nzz5lwylPFHbOK5l3cTNU7A9vM93LJJuHe7+go qvlknWBVY7DOl0zF5x5vedOGuoQv/OwNxT2wV6YvCNHSQudFssZWNZmzxQtcKHAbuoek TeWqQ3EfNXipokk/Hm5Lgldw+pUM3SUSS17kox7j8AdxI6q84seLBmno+VjTRTHJyLXH onLXWDIvq5asksLTeMzCl/xOdmjTOWG3t+YoaA5n+z0jYZalZmzHhHIoRTrrNF/+ZJUf GkMjBEZN3eh6F0jkymK3GmDjaQE7wOaeUl015af6NA2xiUU10YGze4Pqbn0+XYZDLloo 17cg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=qbjnIgYBJ3XppSXgQQQYeUiA93XhGIz1VXZs5463P7w=; b=b3UpS/HALGqGt24cy8UppID+RwY62hd2yTdNiO0h1GwLHI5a9eTZW6FC0DzIxLaIHU 3rVLJTxHOXbhIMpbQMkf/+45frJ52lRqpvGGXv8cCbmWyB39sfj+q46AKZigEiJjkpeK xjI3e2wxARZQxt1AirDTy0JqMTuqCB+T2eTL3qBSsaM9K63oQra5/mNM+SE9WaEkSUar qGA1T/7BaYPcNDaXD5rFsuYI2yC7nOgx7vrKFpPhxFA4NYwknJvJte7TXyyECaZ3by/l 2ZJVKrn/QwSYdFs2vBtiTSLRMCVpKinl7ktr66tLn7N4NvXfQebCB9Vc7ItNH1cr/FaN Ze4w== X-Gm-Message-State: AOAM5317ZkzkVfgOL4PllxLsvFJM+Ip6SkX9gqbswHyZru0ZfDU05UYJ J9bhuttMBzMQM4wf6+qmEg7Fjc7/tCuWMgKZliJyOfTU3JeHYVmVrKPC74BC/KBys6HV5uy1XF9 Al0jwoWbkb7jxAlZfQ1r9DaJnodDbgVxy7YbnYz/peSZq79Ayu79XK8shiSDuRUqUwtrhF478mQ 0MSYw= X-Google-Smtp-Source: ABdhPJz9Ek7cEnnPCPkoDny99Hshm4lGjHn+ctBh/26ElC2yGLSEfafQoXOoVDhsi4tv9Hxiff+bgT7e2TeYLEN4rwTx0w== X-Received: by 2002:a5b:58a:: with SMTP id l10mr2498710ybp.483.1589926977413; Tue, 19 May 2020 15:22:57 -0700 (PDT) Date: Tue, 19 May 2020 15:22:38 -0700 In-Reply-To: <20200519222238.213574-1-makarandsonare@google.com> Message-Id: <20200519222238.213574-3-makarandsonare@google.com> Mime-Version: 1.0 References: <20200519222238.213574-1-makarandsonare@google.com> X-Mailer: git-send-email 2.26.2.761.g0e0b3e54be-goog Subject: [PATCH v2 2/2] KVM: selftests: VMX preemption timer migration test From: Makarand Sonare To: kvm@vger.kernel.org, pshier@google.com, jmattson@google.com Cc: Makarand Sonare Content-Type: text/plain; charset="UTF-8" Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org When a nested VM with a VMX-preemption timer is migrated, verify that the nested VM and its parent VM observe the VMX-preemption timer exit close to the original expiration deadline. Signed-off-by: Makarand Sonare Reviewed-by: Jim Mattson Change-Id: Ia79337c682ee161399525edc34201fad473fc190 --- tools/arch/x86/include/uapi/asm/kvm.h | 1 + tools/testing/selftests/kvm/.gitignore | 1 + tools/testing/selftests/kvm/Makefile | 1 + .../testing/selftests/kvm/include/kvm_util.h | 2 + .../selftests/kvm/include/x86_64/processor.h | 11 +- .../selftests/kvm/include/x86_64/vmx.h | 27 ++ .../kvm/x86_64/vmx_preemption_timer_test.c | 257 ++++++++++++++++++ 7 files changed, 296 insertions(+), 4 deletions(-) create mode 100644 tools/testing/selftests/kvm/x86_64/vmx_preemption_timer_test.c diff --git a/tools/arch/x86/include/uapi/asm/kvm.h b/tools/arch/x86/include/uapi/asm/kvm.h index 3f3f780c8c650..43e24903812c4 100644 --- a/tools/arch/x86/include/uapi/asm/kvm.h +++ b/tools/arch/x86/include/uapi/asm/kvm.h @@ -400,6 +400,7 @@ struct kvm_sync_regs { struct kvm_vmx_nested_state_data { __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE]; __u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE]; + __u64 preemption_timer_deadline; }; struct kvm_vmx_nested_state_hdr { diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index 222e50104296a..f159718f90c0a 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -10,6 +10,7 @@ /x86_64/set_sregs_test /x86_64/smm_test /x86_64/state_test +/x86_64/vmx_preemption_timer_test /x86_64/svm_vmcall_test /x86_64/sync_regs_test /x86_64/vmx_close_while_nested_test diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index c66f4eec34111..780f0c189a7bc 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -20,6 +20,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/platform_info_test TEST_GEN_PROGS_x86_64 += x86_64/set_sregs_test TEST_GEN_PROGS_x86_64 += x86_64/smm_test TEST_GEN_PROGS_x86_64 += x86_64/state_test +TEST_GEN_PROGS_x86_64 += x86_64/vmx_preemption_timer_test TEST_GEN_PROGS_x86_64 += x86_64/svm_vmcall_test TEST_GEN_PROGS_x86_64 += x86_64/sync_regs_test TEST_GEN_PROGS_x86_64 += x86_64/vmx_close_while_nested_test diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h index e244c6ecfc1d5..919e161dd2893 100644 --- a/tools/testing/selftests/kvm/include/kvm_util.h +++ b/tools/testing/selftests/kvm/include/kvm_util.h @@ -314,6 +314,8 @@ void ucall_uninit(struct kvm_vm *vm); void ucall(uint64_t cmd, int nargs, ...); uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc); +#define GUEST_SYNC_ARGS(stage, arg1, arg2, arg3, arg4) \ + ucall(UCALL_SYNC, 6, "hello", stage, arg1, arg2, arg3, arg4) #define GUEST_SYNC(stage) ucall(UCALL_SYNC, 2, "hello", stage) #define GUEST_DONE() ucall(UCALL_DONE, 0) #define __GUEST_ASSERT(_condition, _nargs, _args...) do { \ diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 7428513a4c687..7cb19eca6c72d 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -79,13 +79,16 @@ static inline uint64_t get_desc64_base(const struct desc64 *desc) static inline uint64_t rdtsc(void) { uint32_t eax, edx; - + uint32_t tsc_val; /* * The lfence is to wait (on Intel CPUs) until all previous - * instructions have been executed. + * instructions have been executed. If software requires RDTSC to be + * executed prior to execution of any subsequent instruction, it can + * execute LFENCE immediately after RDTSC */ - __asm__ __volatile__("lfence; rdtsc" : "=a"(eax), "=d"(edx)); - return ((uint64_t)edx) << 32 | eax; + __asm__ __volatile__("lfence; rdtsc; lfence" : "=a"(eax), "=d"(edx)); + tsc_val = ((uint64_t)edx) << 32 | eax; + return tsc_val; } static inline uint64_t rdtscp(uint32_t *aux) diff --git a/tools/testing/selftests/kvm/include/x86_64/vmx.h b/tools/testing/selftests/kvm/include/x86_64/vmx.h index 3d27069b9ed9c..ccff3e6e27048 100644 --- a/tools/testing/selftests/kvm/include/x86_64/vmx.h +++ b/tools/testing/selftests/kvm/include/x86_64/vmx.h @@ -575,6 +575,33 @@ struct vmx_pages { void *eptp; }; +union vmx_basic { + u64 val; + struct { + u32 revision; + u32 size:13, + reserved1:3, + width:1, + dual:1, + type:4, + insouts:1, + ctrl:1, + vm_entry_exception_ctrl:1, + reserved2:7; + }; +}; + +union vmx_ctrl_msr { + u64 val; + struct { + u32 set, clr; + }; +}; + +union vmx_basic basic; +union vmx_ctrl_msr ctrl_pin_rev; +union vmx_ctrl_msr ctrl_exit_rev; + struct vmx_pages *vcpu_alloc_vmx(struct kvm_vm *vm, vm_vaddr_t *p_vmx_gva); bool prepare_for_vmx_operation(struct vmx_pages *vmx); void prepare_vmcs(struct vmx_pages *vmx, void *guest_rip, void *guest_rsp); diff --git a/tools/testing/selftests/kvm/x86_64/vmx_preemption_timer_test.c b/tools/testing/selftests/kvm/x86_64/vmx_preemption_timer_test.c new file mode 100644 index 0000000000000..83e363260e145 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/vmx_preemption_timer_test.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VMX-preemption timer test + * + * Copyright (C) 2020, Google, LLC. + * + * Test to ensure the VM-Enter after migration doesn't + * incorrectly restarts the timer with the full timer + * value instead of partially decayed timer value + * + */ +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include +#include +#include +#include +#include + +#include "test_util.h" + +#include "kvm_util.h" +#include "processor.h" +#include "vmx.h" + +#define VCPU_ID 5 +#define PREEMPTION_TIMER_VALUE 100000000ull +#define PREEMPTION_TIMER_VALUE_THRESHOLD1 80000000ull + +u32 vmx_pt_rate; +bool l2_save_restore_done; +static u64 l2_vmx_pt_start; +volatile u64 l2_vmx_pt_finish; + +void l2_guest_code(void) +{ + u64 vmx_pt_delta; + + vmcall(); + l2_vmx_pt_start = (rdtsc() >> vmx_pt_rate) << vmx_pt_rate; + + /* + * Wait until the 1st threshold has passed + */ + do { + l2_vmx_pt_finish = rdtsc(); + vmx_pt_delta = (l2_vmx_pt_finish - l2_vmx_pt_start) >> + vmx_pt_rate; + } while (vmx_pt_delta < PREEMPTION_TIMER_VALUE_THRESHOLD1); + + /* + * Force L2 through Save and Restore cycle + */ + GUEST_SYNC(1); + + l2_save_restore_done = 1; + + /* + * Now wait for the preemption timer to fire and + * exit to L1 + */ + while ((l2_vmx_pt_finish = rdtsc())) + ; +} + +void l1_guest_code(struct vmx_pages *vmx_pages) +{ +#define L2_GUEST_STACK_SIZE 64 + unsigned long l2_guest_stack[L2_GUEST_STACK_SIZE]; + u64 l1_vmx_pt_start; + u64 l1_vmx_pt_finish; + u64 l1_tsc_deadline, l2_tsc_deadline; + + GUEST_ASSERT(vmx_pages->vmcs_gpa); + GUEST_ASSERT(prepare_for_vmx_operation(vmx_pages)); + GUEST_ASSERT(load_vmcs(vmx_pages)); + GUEST_ASSERT(vmptrstz() == vmx_pages->vmcs_gpa); + + prepare_vmcs(vmx_pages, l2_guest_code, + &l2_guest_stack[L2_GUEST_STACK_SIZE]); + + GUEST_ASSERT(!vmlaunch()); + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_VMCALL); + vmwrite(GUEST_RIP, vmreadz(GUEST_RIP) + 3); + + /* + * Check for Preemption timer support and turn on PIN control + */ + basic.val = rdmsr(MSR_IA32_VMX_BASIC); + ctrl_pin_rev.val = rdmsr(basic.ctrl ? MSR_IA32_VMX_TRUE_PINBASED_CTLS + : MSR_IA32_VMX_PINBASED_CTLS); + ctrl_exit_rev.val = rdmsr(basic.ctrl ? MSR_IA32_VMX_TRUE_EXIT_CTLS + : MSR_IA32_VMX_EXIT_CTLS); + + if (!(ctrl_pin_rev.clr & PIN_BASED_VMX_PREEMPTION_TIMER) || + !(ctrl_exit_rev.clr & VM_EXIT_SAVE_VMX_PREEMPTION_TIMER)) + return; + + GUEST_ASSERT(!vmwrite(PIN_BASED_VM_EXEC_CONTROL, + vmreadz(PIN_BASED_VM_EXEC_CONTROL) | + PIN_BASED_VMX_PREEMPTION_TIMER)); + + GUEST_ASSERT(!vmwrite(VMX_PREEMPTION_TIMER_VALUE, + PREEMPTION_TIMER_VALUE)); + + vmx_pt_rate = rdmsr(MSR_IA32_VMX_MISC) & 0x1F; + + l2_save_restore_done = 0; + + l1_vmx_pt_start = (rdtsc() >> vmx_pt_rate) << vmx_pt_rate; + + GUEST_ASSERT(!vmresume()); + + l1_vmx_pt_finish = rdtsc(); + + /* + * Ensure exit from L2 happens after L2 goes through + * save and restore + */ + GUEST_ASSERT(l2_save_restore_done); + + /* + * Ensure the exit from L2 is due to preemption timer expiry + */ + GUEST_ASSERT(vmreadz(VM_EXIT_REASON) == EXIT_REASON_PREEMPTION_TIMER); + + l1_tsc_deadline = l1_vmx_pt_start + + (PREEMPTION_TIMER_VALUE << vmx_pt_rate); + + l2_tsc_deadline = l2_vmx_pt_start + + (PREEMPTION_TIMER_VALUE << vmx_pt_rate); + + /* + * Sync with the host and pass the l1|l2 pt_expiry_finish times and + * tsc deadlines so that host can verify they are as expected + */ + GUEST_SYNC_ARGS(2, l1_vmx_pt_finish, l1_tsc_deadline, + l2_vmx_pt_finish, l2_tsc_deadline); +} + +void guest_code(struct vmx_pages *vmx_pages) +{ + if (vmx_pages) + l1_guest_code(vmx_pages); + + GUEST_DONE(); +} + +int main(int argc, char *argv[]) +{ + vm_vaddr_t vmx_pages_gva = 0; + + struct kvm_regs regs1, regs2; + struct kvm_vm *vm; + struct kvm_run *run; + struct kvm_x86_state *state; + struct ucall uc; + int stage; + + /* + * AMD currently does not implement any VMX features, so for now we + * just early out. + */ + nested_vmx_check_supported(); + + /* Create VM */ + vm = vm_create_default(VCPU_ID, 0, guest_code); + vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid()); + run = vcpu_state(vm, VCPU_ID); + + vcpu_regs_get(vm, VCPU_ID, ®s1); + + if (kvm_check_cap(KVM_CAP_NESTED_STATE_PREEMPTION_TIMER)) { + vcpu_alloc_vmx(vm, &vmx_pages_gva); + vcpu_args_set(vm, VCPU_ID, 1, vmx_pages_gva); + } else { + pr_info("will skip vmx preemption timer checks\n"); + goto done; + } + + for (stage = 1;; stage++) { + _vcpu_run(vm, VCPU_ID); + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Stage %d: unexpected exit reason: %u (%s),\n", + stage, run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vm, VCPU_ID, &uc)) { + case UCALL_ABORT: + TEST_FAIL("%s at %s:%ld", (const char *)uc.args[0], + __FILE__, uc.args[1]); + /* NOT REACHED */ + case UCALL_SYNC: + break; + case UCALL_DONE: + goto done; + default: + TEST_FAIL("Unknown ucall %lu", uc.cmd); + } + + /* UCALL_SYNC is handled here. */ + TEST_ASSERT(!strcmp((const char *)uc.args[0], "hello") && + uc.args[1] == stage, "Stage %d: Unexpected register values vmexit, got %lx", + stage, (ulong)uc.args[1]); + /* + * If this stage 2 then we should verify the vmx pt expiry + * is as expected + */ + if (stage == 2) { + + pr_info("Stage %d: L1 PT expiry TSC (%lu) , L1 TSC deadline (%lu)\n", + stage, uc.args[2], uc.args[3]); + + pr_info("Stage %d: L2 PT expiry TSC (%lu) , L2 TSC deadline (%lu)\n", + stage, uc.args[4], uc.args[5]); + + /* + * From L1's perspective verify Preemption timer hasn't + * expired too early + */ + + TEST_ASSERT(uc.args[2] >= uc.args[3], + "Stage %d: L1 PT expiry TSC (%lu) < L1 TSC deadline (%lu)", + stage, uc.args[2], uc.args[3]); + + /* + * From L2's perspective verify Preemption timer hasn't + * expired too late + */ + TEST_ASSERT(uc.args[4] < uc.args[5], + "Stage %d: L2 PT expiry TSC (%lu) > L2 TSC deadline (%lu)", + stage, uc.args[4], uc.args[5]); + } + + state = vcpu_save_state(vm, VCPU_ID); + memset(®s1, 0, sizeof(regs1)); + vcpu_regs_get(vm, VCPU_ID, ®s1); + + kvm_vm_release(vm); + + /* Restore state in a new VM. */ + kvm_vm_restart(vm, O_RDWR); + vm_vcpu_add(vm, VCPU_ID); + vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid()); + vcpu_load_state(vm, VCPU_ID, state); + run = vcpu_state(vm, VCPU_ID); + free(state); + + memset(®s2, 0, sizeof(regs2)); + vcpu_regs_get(vm, VCPU_ID, ®s2); + TEST_ASSERT(!memcmp(®s1, ®s2, sizeof(regs2)), + "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx", + (ulong) regs2.rdi, (ulong) regs2.rsi); + } + +done: + kvm_vm_free(vm); +} -- 2.26.2.761.g0e0b3e54be-goog