From patchwork Thu Sep 28 00:19:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13401832 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 32B80E7F14F for ; Thu, 28 Sep 2023 00:20:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229866AbjI1AUK (ORCPT ); Wed, 27 Sep 2023 20:20:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229854AbjI1AUI (ORCPT ); Wed, 27 Sep 2023 20:20:08 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49AD013A for ; Wed, 27 Sep 2023 17:20:06 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id 3f1490d57ef6-d81e9981ff4so18131860276.3 for ; Wed, 27 Sep 2023 17:20:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1695860405; x=1696465205; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=4QGGNsUnXbHlm2535h1KbmRwKOI34J8NkE8WwWAmRM0=; b=jalgCVa0URnqS6ZdjQTQqUbxwtvLy67ddZSgc0ZR01/k9PcOmHDUgW1i5RxcyiCC/5 qFoySJhtbebxR+RPfU32HdJQ44E4P7cSl9Rmc7WA5IHcZrHue7c/kyhy0KECBfD39i22 5gZbIRFQLgEyZUeBY+ji2mUEZMy5bWMLCVicHWczfr2ia2TZ6EhftmlxJAOnNG/tklxP 7FPocL34negDqydY7dMtm3PldAUB/NWY4OEEbYX/wWgiJJjKV8aRuB/IEQ8t54PE8NFA HNFC7sGBmJtphRY5si9fOJX+TqS4QbpdnVBq6T/8mRmlepY+jjrN/YnhbRxEOkkNl53A 5VMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695860405; x=1696465205; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=4QGGNsUnXbHlm2535h1KbmRwKOI34J8NkE8WwWAmRM0=; b=tULkGC4MasMvERw9AtLqWGtWRYfl5BZcYf2EXm8AjnbsKNNOo83Rh3lKoVN4aIO/g2 q2QJ4xPJHmj7YaPd7TcC5y5bPiKde9RuOaU9rmPW/Zll1QQPNCWijKKOjmpXlIt518qU tRyiodlk7jmR4SRRNADOfVzthvNQgcD037spL5PHioXfZyRBoBnb5cbOqmtzLNRuhTs9 oah7LGheYZZucoPTwIMlxBNBAifcTJY9IvC00JKgvzoPJ7+x/bd/aOzpEAeQrQE4IJmM nLYCG5Xx0jQjIayma2YSwnxMmXtXEYtaAqZThDp7YUZSSL70YVIBm3TKbuCaUdR7xL3K B4YA== X-Gm-Message-State: AOJu0YxeRDBSMrgHjMXtjP4oUwFvRQDfknwhaF6kmWwooX2H06ChTZnP Kr650eutcZwSdNgVdPLuVOb/B7XQhVk= X-Google-Smtp-Source: AGHT+IEBfyu8iwbl726nGZ0r1f2jWkIfXapTcl/HjZ1vtmHkcySW81vMihJO8Ki3Dn5u2RZ7E2kBPhAtGdk= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6902:1613:b0:d80:ff9:d19e with SMTP id bw19-20020a056902161300b00d800ff9d19emr55418ybb.9.1695860405485; Wed, 27 Sep 2023 17:20:05 -0700 (PDT) Reply-To: Sean Christopherson Date: Wed, 27 Sep 2023 17:19:54 -0700 In-Reply-To: <20230928001956.924301-1-seanjc@google.com> Mime-Version: 1.0 References: <20230928001956.924301-1-seanjc@google.com> X-Mailer: git-send-email 2.42.0.582.g8ccd20d70d-goog Message-ID: <20230928001956.924301-4-seanjc@google.com> Subject: [PATCH 3/5] KVM: selftests: Touch relevant XSAVE state in guest for state test From: Sean Christopherson To: Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Sean Christopherson , Paolo Bonzini , Shuah Khan , Nathan Chancellor , Nick Desaulniers Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-kselftest@vger.kernel.org, llvm@lists.linux.dev, Tyler Stachecki , Leonardo Bras Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Modify support XSAVE state in the "state test's" guest code so that saving and loading state via KVM_{G,S}ET_XSAVE actually does something useful, i.e. so that xstate_bv in XSAVE state isn't empty. Punt on BNDCSR for now, it's easier to just stuff that xfeature from the host side. Signed-off-by: Sean Christopherson --- .../selftests/kvm/include/x86_64/processor.h | 14 ++++ .../testing/selftests/kvm/x86_64/state_test.c | 77 +++++++++++++++++++ 2 files changed, 91 insertions(+) diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h index 4fd042112526..6f66861175ad 100644 --- a/tools/testing/selftests/kvm/include/x86_64/processor.h +++ b/tools/testing/selftests/kvm/include/x86_64/processor.h @@ -68,6 +68,12 @@ struct xstate { #define XFEATURE_MASK_OPMASK BIT_ULL(5) #define XFEATURE_MASK_ZMM_Hi256 BIT_ULL(6) #define XFEATURE_MASK_Hi16_ZMM BIT_ULL(7) +#define XFEATURE_MASK_PT BIT_ULL(8) +#define XFEATURE_MASK_PKRU BIT_ULL(9) +#define XFEATURE_MASK_PASID BIT_ULL(10) +#define XFEATURE_MASK_CET_USER BIT_ULL(11) +#define XFEATURE_MASK_CET_KERNEL BIT_ULL(12) +#define XFEATURE_MASK_LBR BIT_ULL(15) #define XFEATURE_MASK_XTILE_CFG BIT_ULL(17) #define XFEATURE_MASK_XTILE_DATA BIT_ULL(18) @@ -147,6 +153,7 @@ struct kvm_x86_cpu_feature { #define X86_FEATURE_CLWB KVM_X86_CPU_FEATURE(0x7, 0, EBX, 24) #define X86_FEATURE_UMIP KVM_X86_CPU_FEATURE(0x7, 0, ECX, 2) #define X86_FEATURE_PKU KVM_X86_CPU_FEATURE(0x7, 0, ECX, 3) +#define X86_FEATURE_OSPKE KVM_X86_CPU_FEATURE(0x7, 0, ECX, 4) #define X86_FEATURE_LA57 KVM_X86_CPU_FEATURE(0x7, 0, ECX, 16) #define X86_FEATURE_RDPID KVM_X86_CPU_FEATURE(0x7, 0, ECX, 22) #define X86_FEATURE_SGX_LC KVM_X86_CPU_FEATURE(0x7, 0, ECX, 30) @@ -553,6 +560,13 @@ static inline void xsetbv(u32 index, u64 value) __asm__ __volatile__("xsetbv" :: "a" (eax), "d" (edx), "c" (index)); } +static inline void wrpkru(u32 pkru) +{ + /* Note, ECX and EDX are architecturally required to be '0'. */ + asm volatile(".byte 0x0f,0x01,0xef\n\t" + : : "a" (pkru), "c"(0), "d"(0)); +} + static inline struct desc_ptr get_gdt(void) { struct desc_ptr gdt; diff --git a/tools/testing/selftests/kvm/x86_64/state_test.c b/tools/testing/selftests/kvm/x86_64/state_test.c index 4c4925a8ab45..df3e93df4343 100644 --- a/tools/testing/selftests/kvm/x86_64/state_test.c +++ b/tools/testing/selftests/kvm/x86_64/state_test.c @@ -139,6 +139,83 @@ static void vmx_l1_guest_code(struct vmx_pages *vmx_pages) static void __attribute__((__flatten__)) guest_code(void *arg) { GUEST_SYNC(1); + + if (this_cpu_has(X86_FEATURE_XSAVE)) { + uint64_t supported_xcr0 = this_cpu_supported_xcr0(); + uint8_t buffer[4096]; + + memset(buffer, 0xcc, sizeof(buffer)); + + set_cr4(get_cr4() | X86_CR4_OSXSAVE); + GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE)); + + xsetbv(0, xgetbv(0) | supported_xcr0); + + /* + * Modify state for all supported xfeatures to take them out of + * their "init" state, i.e. to make them show up in XSTATE_BV. + * + * Note off-by-default features, e.g. AMX, are out of scope for + * this particular testcase as they have a different ABI. + */ + GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_FP); + asm volatile ("fincstp"); + + GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_SSE); + asm volatile ("vmovdqu %0, %%xmm0" :: "m" (buffer)); + + if (supported_xcr0 & XFEATURE_MASK_YMM) + asm volatile ("vmovdqu %0, %%ymm0" :: "m" (buffer)); + + if (supported_xcr0 & XFEATURE_MASK_AVX512) { + asm volatile ("kmovq %0, %%k1" :: "r" (-1ull)); + asm volatile ("vmovupd %0, %%zmm0" :: "m" (buffer)); + asm volatile ("vmovupd %0, %%zmm16" :: "m" (buffer)); + } + + if (this_cpu_has(X86_FEATURE_MPX)) { + uint64_t bounds[2] = { 10, 0xffffffffull }; + uint64_t output[2] = { }; + + GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_BNDREGS); + GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_BNDCSR); + + /* + * Don't bother trying to get BNDCSR into the INUSE + * state. MSR_IA32_BNDCFGS doesn't count as it isn't + * managed via XSAVE/XRSTOR, and BNDCFGU can only be + * modified by XRSTOR. Stuffing XSTATE_BV in the host + * is simpler than doing XRSTOR here in the guest. + * + * However, temporarily enable MPX in BNDCFGS so that + * BNDMOV actually loads BND1. If MPX isn't *fully* + * enabled, all MPX instructions are treated as NOPs. + * + * Hand encode "bndmov (%rax),%bnd1" as support for MPX + * mnemonics/registers has been removed from gcc and + * clang (and was never fully supported by clang). + */ + wrmsr(MSR_IA32_BNDCFGS, BIT_ULL(0)); + asm volatile (".byte 0x66,0x0f,0x1a,0x08" :: "a" (bounds)); + /* + * Hand encode "bndmov %bnd1, (%rax)" to sanity check + * that BND1 actually got loaded. + */ + asm volatile (".byte 0x66,0x0f,0x1b,0x08" :: "a" (output)); + wrmsr(MSR_IA32_BNDCFGS, 0); + + GUEST_ASSERT_EQ(bounds[0], output[0]); + GUEST_ASSERT_EQ(bounds[1], output[1]); + } + if (this_cpu_has(X86_FEATURE_PKU)) { + GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_PKRU); + set_cr4(get_cr4() | X86_CR4_PKE); + GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSPKE)); + + wrpkru(-1u); + } + } + GUEST_SYNC(2); if (arg) {