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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0A6BDC433EF for ; Tue, 17 May 2022 01:14:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235898AbiEQBOL (ORCPT ); Mon, 16 May 2022 21:14:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51930 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229561AbiEQBOH (ORCPT ); Mon, 16 May 2022 21:14:07 -0400 Received: from mail-yb1-xb2f.google.com (mail-yb1-xb2f.google.com [IPv6:2607:f8b0:4864:20::b2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9DFAC40928; Mon, 16 May 2022 18:14:06 -0700 (PDT) Received: by mail-yb1-xb2f.google.com with SMTP id r1so29963762ybo.7; Mon, 16 May 2022 18:14:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Krh36ViT/EwDdvnp42Kcg/9QiROI+wYenJfQpSBh8DQ=; b=dZ0jQ9xFO9MEBQYlRmAuN309bWDTIKOAEWzH10mbYlxK3A92D3O0rHe3NMpGuuQRQ0 82bXfjvfZbU8U3eVvx/0QD4KI+iKYr756RlYNR6+VTLCwjM+kkGTBPSXnaMWH3stcIhY vHxweQPMbfB2eifacLq1uvr8DRxV1oFRo9vlvfHhreO9osahVcApnPBYPyvDlMUbCsV8 G+F3cLdAzLnhtRB7IAt8X+y9WfkVbQLtMU5rMFylehhZezTHqvuiNzVGAyB86G4/qMCe 172JNlMOqmXe+aSUG0Ti93KH8Ky0IOH8nJ7VpS0nsgyOJUT6597M2MIhN1IUXsI4fyy3 f2Vw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Krh36ViT/EwDdvnp42Kcg/9QiROI+wYenJfQpSBh8DQ=; b=bo7hlcxO/eO/rssHf5vIysaLWaAFBRy/6KoCbsdLMEFHb7bop2fQdeUEmkHt9qiZOM +/WaRRaPXbPeKPTqLcgr4o3slT83dvxn+LtkuttkuRdTnbLDbs3WHk6RhIkTuJ7t+br7 bmBNbMeBMGFYf8q7o+lav3/bK7Nll/C4wKHi6vCnxsPJakiZpQYn/P6WsSrISTQP5qTT 4YhGLP8Gw0MvYPhikhbTaFeIF7UoRyAlLKYdTluKZlDKGUlFJi7NENYxvnUeCb3ixgxU ixJ7zop8Tcb88rPE2RMngDLuWuCdgjmcu0SXI9khGDc/bVxz3keKc0PyMcJCVz1cuNQz RRdQ== X-Gm-Message-State: AOAM532+ZUXA7fy11IatRMAglrjJxsw2wmhZBfBvwGGmp8zUyomjyz5v uuoA/ThIjkSYYNjfqtVuj/LjLv+FXtoT5EV4kkA= X-Google-Smtp-Source: ABdhPJyFdaX9VMqmdftxmEICDY2lizLH2P+RWV4/NuazfAIT5DH3J4F0SfPEA0zhjUDb0Rx58XTM5r2HrA5UMLS+7TQ= X-Received: by 2002:a25:7694:0:b0:64d:b38b:40ec with SMTP id r142-20020a257694000000b0064db38b40ecmr6827973ybc.526.1652750045900; Mon, 16 May 2022 18:14:05 -0700 (PDT) MIME-Version: 1.0 References: <20220503150735.32723-1-jiangshanlai@gmail.com> <20220503150735.32723-4-jiangshanlai@gmail.com> In-Reply-To: From: Lai Jiangshan Date: Tue, 17 May 2022 09:13:54 +0800 Message-ID: Subject: Re: [PATCH V2 3/7] KVM: X86/MMU: Link PAE root pagetable with its children To: David Matlack Cc: LKML , "open list:KERNEL VIRTUAL MACHINE FOR MIPS (KVM/mips)" , Paolo Bonzini , Sean Christopherson , Lai Jiangshan , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , X86 ML , "H. Peter Anvin" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, May 17, 2022 at 8:01 AM David Matlack wrote: > > On Tue, May 03, 2022 at 11:07:31PM +0800, Lai Jiangshan wrote: > > From: Lai Jiangshan > > > > When special shadow pages are activated, link_shadow_page() might link > > a special shadow pages which is the PAE root for PAE paging with its > > children. > > > > Add make_pae_pdpte() to handle it. > > > > The code is not activated since special shadow pages are not activated > > yet. > > > > Signed-off-by: Lai Jiangshan > > --- > > arch/x86/kvm/mmu/mmu.c | 6 +++++- > > arch/x86/kvm/mmu/spte.c | 7 +++++++ > > arch/x86/kvm/mmu/spte.h | 1 + > > 3 files changed, 13 insertions(+), 1 deletion(-) > > > > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > > index 126f0cd07f98..3fe70ad3bda2 100644 > > --- a/arch/x86/kvm/mmu/mmu.c > > +++ b/arch/x86/kvm/mmu/mmu.c > > @@ -2277,7 +2277,11 @@ static void link_shadow_page(struct kvm_vcpu *vcpu, u64 *sptep, > > > > BUILD_BUG_ON(VMX_EPT_WRITABLE_MASK != PT_WRITABLE_MASK); > > > > - spte = make_nonleaf_spte(sp->spt, sp_ad_disabled(sp)); > > + if (unlikely(sp->role.level == PT32_ROOT_LEVEL && > > + vcpu->arch.mmu->root_role.level == PT32E_ROOT_LEVEL)) > > + spte = make_pae_pdpte(sp->spt); > > + else > > + spte = make_nonleaf_spte(sp->spt, sp_ad_disabled(sp)); > > > > mmu_spte_set(sptep, spte); > > > > diff --git a/arch/x86/kvm/mmu/spte.c b/arch/x86/kvm/mmu/spte.c > > index 75c9e87d446a..ccd9267a58ca 100644 > > --- a/arch/x86/kvm/mmu/spte.c > > +++ b/arch/x86/kvm/mmu/spte.c > > @@ -251,6 +251,13 @@ u64 make_huge_page_split_spte(u64 huge_spte, int huge_level, int index) > > return child_spte; > > } > > > > +u64 make_pae_pdpte(u64 *child_pt) > > +{ > > + /* The only ignore bits in PDPTE are 11:9. */ > > + BUILD_BUG_ON(!(GENMASK(11,9) & SPTE_MMU_PRESENT_MASK)); > > + return __pa(child_pt) | PT_PRESENT_MASK | SPTE_MMU_PRESENT_MASK | > > + shadow_me_value; > > If I'm reading mmu_alloc_{direct,shadow}_roots() correctly, PAE page > directories just get: root | PT_PRESENT_MASK | shadow_me_value. Is there > a reason to add SPTE_MMU_PRESENT_MASK or am I misreading the code? Because it has a struct kvm_mmu_page associated with it now. sp->spt[i] requires SPTE_MMU_PRESENT_MASK if it is present. > > > +} > > > > u64 make_nonleaf_spte(u64 *child_pt, bool ad_disabled) > > { > > diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h > > index fbbab180395e..09a7e4ba017a 100644 > > --- a/arch/x86/kvm/mmu/spte.h > > +++ b/arch/x86/kvm/mmu/spte.h > > @@ -413,6 +413,7 @@ bool make_spte(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, > > u64 old_spte, bool prefetch, bool can_unsync, > > bool host_writable, u64 *new_spte); > > u64 make_huge_page_split_spte(u64 huge_spte, int huge_level, int index); > > +u64 make_pae_pdpte(u64 *child_pt); > > u64 make_nonleaf_spte(u64 *child_pt, bool ad_disabled); > > u64 make_mmio_spte(struct kvm_vcpu *vcpu, u64 gfn, unsigned int access); > > u64 mark_spte_for_access_track(u64 spte); > > -- > > 2.19.1.6.gb485710b > >