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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 9BD9EC433E7 for ; Tue, 1 Sep 2020 13:05:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7B3B72067C for ; Tue, 1 Sep 2020 13:05:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="lKxgZz62" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727901AbgIANEb (ORCPT ); Tue, 1 Sep 2020 09:04:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727061AbgIALzS (ORCPT ); Tue, 1 Sep 2020 07:55:18 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 52B1CC061244; Tue, 1 Sep 2020 04:55:09 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id o20so638518pfp.11; Tue, 01 Sep 2020 04:55:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=A6+zZK0PRKc1I+vce+8JY6xxs7Mg0NJgZr5FU/ZHS1w=; b=lKxgZz62BU3j99HgKaMmS/kCvom0NQclIiW3BMeCVMOx546mVt7GmWi2yH1oYB2+0C gQcDgTHmMr27FGuNwZzHoJFeZofywU7V1kFwbSTY90VH9LNAZYU/jXdcTNfp/ViWmz2/ KxqR2zXOuyX2hsRiv19TGMVtaVaWrn1onLTxaFyk5QddY2wzCTbhRAtQHEyc8Ub0p/qu GaE64kRyCCDlg3rBf9f5mXSATnbtYB7B1uShIoOLX2PycNd1X0PBoLNqxUrONjN5lpio J+rSHfLBE5fqPt47o0lwRGKxOMLMLzbamV9uKurjgVsP7z3KIrHeCKL/3YGL8Bg1gXsv UuDw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=A6+zZK0PRKc1I+vce+8JY6xxs7Mg0NJgZr5FU/ZHS1w=; b=cIzFQUXMLO3ZEkGn2TZnDJxtc+mvi5MH6rtrSnuSyY2H/VtHI8/nikfsrHal0o6i6L v5UIAACze8JrcvYQPFYTB8iXzWkMDGSNVMCkbt2txkrkVmOKF8IMR8Q/4F2I2O+ZGmZK WB6EDBm0Q5pMBzoZJDsCJoZzAlOAV/+8CzZhzBHQ71ic+4ZJEAhN7B7BOu6mQLATo2Bq T+PvtpDLqXtKli65G2GOngAeq192WWXj8LpSxTQf9SBHsWi7cwKmhSbS6Zxe1CAwdLB6 UZ5BLpqNS74Mxn1Q406d7qIhFk+XkRe4kTRwj5bnfbqiX/xoEqoN03x2RzOtX14VTqBF DxOg== X-Gm-Message-State: AOAM533KnytxOWY8H1zfTquDTbPR8oerxhfLHUL3j45VvK7HsR54BtQI IfglCo1zuGKhPOoOlKK1xh3MM4LrFIE= X-Google-Smtp-Source: ABdhPJzv9nDY12Kx6kNi2WR6XHoPB47fiHDLEBw9WzZGmJXBQV1jqv719wSs1cSwwcVUSJhPfOoWyA== X-Received: by 2002:a62:6503:: with SMTP id z3mr1497322pfb.132.1598961308884; Tue, 01 Sep 2020 04:55:08 -0700 (PDT) Received: from localhost.localdomain ([203.205.141.53]) by smtp.gmail.com with ESMTPSA id z17sm1737531pfq.38.2020.09.01.04.55.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Sep 2020 04:55:07 -0700 (PDT) From: yulei.kernel@gmail.com X-Google-Original-From: yuleixzhang@tencent.com To: pbonzini@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, sean.j.christopherson@intel.com, jmattson@google.com, junaids@google.com, bgardon@google.com, vkuznets@redhat.com, xiaoguangrong.eric@gmail.com, kernellwp@gmail.com, lihaiwei.kernel@gmail.com, Yulei Zhang , Yulei Zhang Subject: [RFC V2 5/9] Modify the page fault path to meet the direct build EPT requirement Date: Tue, 1 Sep 2020 19:56:02 +0800 Message-Id: <4a5c67fea73a18661cf4918860606e5a19f11b78.1598868204.git.yulei.kernel@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yulei Zhang Refine the fast page fault code so that it can be used in either normal ept mode or direct build EPT mode. Signed-off-by: Yulei Zhang --- arch/x86/kvm/mmu/mmu.c | 28 ++++++++++++++++++++-------- 1 file changed, 20 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index f2124f52b286..fda6c4196854 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -3443,12 +3443,13 @@ static bool page_fault_can_be_fast(u32 error_code) * someone else modified the SPTE from its original value. */ static bool -fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, +fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, gpa_t gpa, u64 *sptep, u64 old_spte, u64 new_spte) { gfn_t gfn; - WARN_ON(!sp->role.direct); + WARN_ON(!vcpu->arch.direct_build_tdp && + (!sptep_to_sp(sptep)->role.direct)); /* * Theoretically we could also set dirty bit (and flush TLB) here in @@ -3470,7 +3471,8 @@ fast_pf_fix_direct_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, * The gfn of direct spte is stable since it is * calculated by sp->gfn. */ - gfn = kvm_mmu_page_get_gfn(sp, sptep - sp->spt); + + gfn = gpa >> PAGE_SHIFT; kvm_vcpu_mark_page_dirty(vcpu, gfn); } @@ -3498,10 +3500,10 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u32 error_code) { struct kvm_shadow_walk_iterator iterator; - struct kvm_mmu_page *sp; bool fault_handled = false; u64 spte = 0ull; uint retry_count = 0; + int pte_level = 0; if (!page_fault_can_be_fast(error_code)) return false; @@ -3515,8 +3517,15 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, if (!is_shadow_present_pte(spte)) break; - sp = sptep_to_sp(iterator.sptep); - if (!is_last_spte(spte, sp->role.level)) + if (iterator.level < PG_LEVEL_4K) + pte_level = PG_LEVEL_4K; + else + pte_level = iterator.level; + + WARN_ON(!vcpu->arch.direct_build_tdp && + (pte_level != sptep_to_sp(iterator.sptep)->role.level)); + + if (!is_last_spte(spte, pte_level)) break; /* @@ -3559,7 +3568,7 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * * See the comments in kvm_arch_commit_memory_region(). */ - if (sp->role.level > PG_LEVEL_4K) + if (pte_level > PG_LEVEL_4K) break; } @@ -3573,7 +3582,7 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, * since the gfn is not stable for indirect shadow page. See * Documentation/virt/kvm/locking.rst to get more detail. */ - fault_handled = fast_pf_fix_direct_spte(vcpu, sp, + fault_handled = fast_pf_fix_direct_spte(vcpu, cr2_or_gpa, iterator.sptep, spte, new_spte); if (fault_handled) @@ -4106,6 +4115,9 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code, if (fast_page_fault(vcpu, gpa, error_code)) return RET_PF_RETRY; + if (vcpu->arch.direct_build_tdp) + return RET_PF_EMULATE; + r = mmu_topup_memory_caches(vcpu, false); if (r) return r; -- 2.17.1