From patchwork Mon Dec 5 23:23:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vishal Annapurve X-Patchwork-Id: 13065193 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 BC4E9C636F9 for ; Mon, 5 Dec 2022 23:23:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231888AbiLEXXz (ORCPT ); Mon, 5 Dec 2022 18:23:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44090 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231715AbiLEXXv (ORCPT ); Mon, 5 Dec 2022 18:23:51 -0500 Received: from mail-pg1-x54a.google.com (mail-pg1-x54a.google.com [IPv6:2607:f8b0:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96DBE1835C for ; Mon, 5 Dec 2022 15:23:50 -0800 (PST) Received: by mail-pg1-x54a.google.com with SMTP id i19-20020a63e913000000b004705d1506a6so11004803pgh.13 for ; Mon, 05 Dec 2022 15:23:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=bJsitMNrFwlWnkUPP+bzm0yFNlRi9o93p/cQJywTOXc=; b=BeFPFGkoIaSJW4OwyhtPykbuDKK8eg9FRG8ZrYy513qt1mteOhpFvR+ZPC6SOxjT0E Ee2a1RsDEA/8rV9K6WEagcDYhhMxcc3Yi+B2FRdqowFjfFx0ZExIpmGTZ25uFRzhVLSE c9rrECLvcTpVHxi/O5g0MwFLcMlc5qK29gKnctJZIQPcsuR1Wdj2Zb2xBdSKYN5GaCXb X9TW7aLUFnXHDIXxbaA8Wq52e/WoFR3oW6XsdtdF00zBsQ3ZSCRV+wyRlC6C2aRSHECH BJRtfzsp8EUTLT84jRRMN/9ysYGTzHzE9yuLYCvBVSPlM4qkJZSMPznYV6Eatrb2gZXV 9qVw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=bJsitMNrFwlWnkUPP+bzm0yFNlRi9o93p/cQJywTOXc=; b=LEaQb+R8mrLqjhNnbAAfhmSavd6dUBEkeXOLlenbBS/vI5TOz8r9p65TFXSm5nrXK8 yGpKI2lvvxzBCvbgGC5YG58VHKTP5QvWxp+31JYCwfpM3HlXEchNW+LhEXVli65sj1dG r5CpVB/Q9i0mjisiUete4yWtz7Cm3L+KfYNRbrhZOfcar6SjcR79mtBQ4BhPC5DVAwS1 EAM0l+0vRh8ASQkZszgNmy8QdemvD57w6wduifmKTUgApz7bUQmFtSaXnpsJ+74EMiBP 1phWhJj94j8+ykJBbZudlZGobZk4LUSW2aJM9GJbcl315uQLiaTfxjXtDchMKjy3Bfo7 7OnA== X-Gm-Message-State: ANoB5pmCf/26IMVB25TLyyCKORjCmgw3XQGtCSxDamjbjKGUzbM9zgbw SCOk/2LMHXh36ujCEG63lb6X/actwG3gK3BE X-Google-Smtp-Source: AA0mqf70IPLrIk8kUk34OCEAZ8JdYwWW/LqbN4So04STHjgiA+SBHYffgYaXuzj2UbySbdE8Lbsi9J5g63+gR9VL X-Received: from vannapurve2.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:41f8]) (user=vannapurve job=sendgmr) by 2002:a17:90a:2dc8:b0:219:baef:3ba with SMTP id q8-20020a17090a2dc800b00219baef03bamr11402807pjm.6.1670282630094; Mon, 05 Dec 2022 15:23:50 -0800 (PST) Date: Mon, 5 Dec 2022 23:23:36 +0000 In-Reply-To: <20221205232341.4131240-1-vannapurve@google.com> Mime-Version: 1.0 References: <20221205232341.4131240-1-vannapurve@google.com> X-Mailer: git-send-email 2.39.0.rc0.267.gcb52ba06e7-goog Message-ID: <20221205232341.4131240-2-vannapurve@google.com> Subject: [V2 PATCH 1/6] KVM: x86: Add support for testing private memory From: Vishal Annapurve To: x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, shuah@kernel.org, yang.zhong@intel.com, ricarkol@google.com, aaronlewis@google.com, wei.w.wang@intel.com, kirill.shutemov@linux.intel.com, corbet@lwn.net, hughd@google.com, jlayton@kernel.org, bfields@fieldses.org, akpm@linux-foundation.org, chao.p.peng@linux.intel.com, yu.c.zhang@linux.intel.com, jun.nakajima@intel.com, dave.hansen@intel.com, michael.roth@amd.com, qperret@google.com, steven.price@arm.com, ak@linux.intel.com, david@redhat.com, luto@kernel.org, vbabka@suse.cz, marcorr@google.com, erdemaktas@google.com, pgonda@google.com, nikunj@amd.com, seanjc@google.com, diviness@google.com, maz@kernel.org, dmatlack@google.com, axelrasmussen@google.com, maciej.szmigiero@oracle.com, mizhang@google.com, bgardon@google.com, ackerleytng@google.com, Vishal Annapurve Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Introduce HAVE_KVM_PRIVATE_MEM_TESTING config to be able to test fd based approach to support private memory with non-confidential selftest VMs. To support this testing few important aspects need to be considered from the perspective of selftests - * KVM needs to know whether the access from guest VM is private or shared. Confidential VMs (SNP/TDX) carry a dedicated bit in gpa that can be used by KVM to deduce the nature of the access. Non-confidential VMs don't have mechanism to carry/convey such an information to KVM. So KVM just relies on what attributes are set by userspace VMM keeping the userspace VMM in the TCB for the testing purposes. * arch_private_mem_supported is updated to allow private memory logic to work with non-confidential vm selftests. Signed-off-by: Vishal Annapurve --- arch/x86/kvm/mmu/mmu_internal.h | 6 +++++- virt/kvm/Kconfig | 4 ++++ virt/kvm/kvm_main.c | 3 ++- 3 files changed, 11 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h index 5ccf08183b00..e2f508db0b6e 100644 --- a/arch/x86/kvm/mmu/mmu_internal.h +++ b/arch/x86/kvm/mmu/mmu_internal.h @@ -263,6 +263,8 @@ enum { static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u32 err, bool prefetch) { + bool is_tdp = likely(vcpu->arch.mmu->page_fault == kvm_tdp_page_fault); + struct kvm_page_fault fault = { .addr = cr2_or_gpa, .error_code = err, @@ -272,13 +274,15 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, .rsvd = err & PFERR_RSVD_MASK, .user = err & PFERR_USER_MASK, .prefetch = prefetch, - .is_tdp = likely(vcpu->arch.mmu->page_fault == kvm_tdp_page_fault), + .is_tdp = is_tdp, .nx_huge_page_workaround_enabled = is_nx_huge_page_enabled(vcpu->kvm), .max_level = KVM_MAX_HUGEPAGE_LEVEL, .req_level = PG_LEVEL_4K, .goal_level = PG_LEVEL_4K, + .is_private = IS_ENABLED(CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING) && is_tdp && + kvm_mem_is_private(vcpu->kvm, cr2_or_gpa >> PAGE_SHIFT), }; int r; diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index d605545d6dd1..1e326367a21c 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -92,3 +92,7 @@ config HAVE_KVM_PM_NOTIFIER config HAVE_KVM_RESTRICTED_MEM bool + +config HAVE_KVM_PRIVATE_MEM_TESTING + bool "Private memory selftests" + depends on HAVE_KVM_MEMORY_ATTRIBUTES && HAVE_KVM_RESTRICTED_MEM diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ac835fc77273..d2d829d23442 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1262,7 +1262,8 @@ int __weak kvm_arch_create_vm_debugfs(struct kvm *kvm) bool __weak kvm_arch_has_private_mem(struct kvm *kvm) { - return false; + return IS_ENABLED(CONFIG_HAVE_KVM_PRIVATE_MEM_TESTING); + } static struct kvm *kvm_create_vm(unsigned long type, const char *fdname)