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 F3B04C27C42 for ; Wed, 16 Aug 2023 21:45:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346629AbjHPVow (ORCPT ); Wed, 16 Aug 2023 17:44:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346660AbjHPVob (ORCPT ); Wed, 16 Aug 2023 17:44:31 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1270C273A for ; Wed, 16 Aug 2023 14:44:27 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id 41be03b00d2f7-5646e695ec1so10509063a12.1 for ; Wed, 16 Aug 2023 14:44:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1692222266; x=1692827066; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=7aJZe8+CPSzm1uQ31UW15d4LYpFiin9OTY1YmG5+H2o=; b=5FnFmr0h3gjr+/vpDpnpYnX5gIhkCQ4jEG1gSS7nJJAppTjOcaxDoFqgcIXvY7h/d2 a0Z47gC4syP1XGsTzyh5eMyJLZbwtKk3CUWhffe/MVgdDpWHQAuEIm1I5rQHuRHFYYMf nM5zBOKmA3EySxHeLEUE5+NIC03+C0EyBB+5/L0q52W0pvV+wkx34CLyQpHOzOjRnD9B jJ4qq54VpzsihbVPJ2cNOpCllRUgbLASkaNsh45bNmQMTg9OBKIZuW9WvD/b/f4VgPWJ KHXEETo1KapA27A1ayPOROfeBJdqOYlYOZ/Bl0RzPNZXUGaF2Y9pIpzesy8dGvI7mnjM CjXA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692222266; x=1692827066; 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=7aJZe8+CPSzm1uQ31UW15d4LYpFiin9OTY1YmG5+H2o=; b=bnvJaFxTE0Nk7rh2d/2YWb7nrJPnN7tasz7AKZI5gx209kH87LpdETEq8gOpEev9A3 GuY9F01YIelN8H5BNCwiOmWTGv4nVO+hP2KnJSdq1kuNd9UvuR8lMi8gw0EhG+qhc9xp 2Z0Gyf1uLoBwoPQP4iCO2s5uOnLI+CRGXfNnN6b3TOe+ZzseF1XoJ8VuR3mjTDMaJhdb vqiGoK5dgvBMHxObXaJR01UsEyAECPelEk0aCoXzTd8JZrSx3iranehl/JMpo81dR4rY qOS6JYZe64VFUfYqK0EES+uyuWBOb4f8rR3ae3Rabef5rbGUXkRgjvPimgNMvGcmGnVy KzcA== X-Gm-Message-State: AOJu0YzmW3LFhkSXntKwhgaJjPz+GvXSLDP+ybTfVTqQ8jIanv5Te/XA edH+x+JPKEnk+I7aEsDUcnTHl/Wx1ZI= X-Google-Smtp-Source: AGHT+IHQ5b8bXt+vgSEAeURRHYKMC28i0AKm9/yVRY0BGqX1G7iOdGibZ10hhforoeesRKRFiCL3cxRmWJI= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a63:715b:0:b0:567:c791:ce64 with SMTP id b27-20020a63715b000000b00567c791ce64mr159671pgn.8.1692222266642; Wed, 16 Aug 2023 14:44:26 -0700 (PDT) Date: Wed, 16 Aug 2023 14:44:24 -0700 In-Reply-To: <20230719144131.29052-6-binbin.wu@linux.intel.com> Mime-Version: 1.0 References: <20230719144131.29052-1-binbin.wu@linux.intel.com> <20230719144131.29052-6-binbin.wu@linux.intel.com> Message-ID: Subject: Re: [PATCH v10 5/9] KVM: x86: Virtualize CR3.LAM_{U48,U57} From: Sean Christopherson To: Binbin Wu Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, chao.gao@intel.com, kai.huang@intel.com, David.Laight@aculab.com, robert.hu@linux.intel.com, guang.zeng@intel.com Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 19, 2023, Binbin Wu wrote: > Add support to allow guests to set two new CR3 non-address control bits for > guests to enable the new Intel CPU feature Linear Address Masking (LAM) on user > pointers. Same feedback as the LAM_SUP patch. > --- > arch/x86/kvm/cpuid.h | 3 +++ > arch/x86/kvm/mmu.h | 8 ++++++++ > arch/x86/kvm/mmu/mmu.c | 2 +- > arch/x86/kvm/vmx/vmx.c | 3 ++- > 4 files changed, 14 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h > index 8b26d946f3e3..274f41d2250b 100644 > --- a/arch/x86/kvm/cpuid.h > +++ b/arch/x86/kvm/cpuid.h > @@ -285,6 +285,9 @@ static __always_inline bool guest_can_use(struct kvm_vcpu *vcpu, > > static inline bool kvm_vcpu_is_legal_cr3(struct kvm_vcpu *vcpu, unsigned long cr3) > { > + if (guest_can_use(vcpu, X86_FEATURE_LAM)) > + cr3 &= ~(X86_CR3_LAM_U48 | X86_CR3_LAM_U57); > + > return kvm_vcpu_is_legal_gpa(vcpu, cr3); > } > > diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h > index 92d5a1924fc1..e92395e6b876 100644 > --- a/arch/x86/kvm/mmu.h > +++ b/arch/x86/kvm/mmu.h > @@ -144,6 +144,14 @@ static inline unsigned long kvm_get_active_pcid(struct kvm_vcpu *vcpu) > return kvm_get_pcid(vcpu, kvm_read_cr3(vcpu)); > } > > +static inline unsigned long kvm_get_active_cr3_lam_bits(struct kvm_vcpu *vcpu) > +{ > + if (!guest_can_use(vcpu, X86_FEATURE_LAM)) > + return 0; > + > + return kvm_read_cr3(vcpu) & (X86_CR3_LAM_U48 | X86_CR3_LAM_U57); > +} > + > static inline void kvm_mmu_load_pgd(struct kvm_vcpu *vcpu) > { > u64 root_hpa = vcpu->arch.mmu->root.hpa; > diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c > index ec169f5c7dce..0285536346c1 100644 > --- a/arch/x86/kvm/mmu/mmu.c > +++ b/arch/x86/kvm/mmu/mmu.c > @@ -3819,7 +3819,7 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu) > hpa_t root; > > root_pgd = kvm_mmu_get_guest_pgd(vcpu, mmu); > - root_gfn = root_pgd >> PAGE_SHIFT; > + root_gfn = (root_pgd & __PT_BASE_ADDR_MASK) >> PAGE_SHIFT; And as mentioned previously, this should be in the patch that adds __PT_BASE_ADDR_MASK. > if (mmu_check_root(vcpu, root_gfn)) > return 1; > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index a0d6ea87a2d0..bcee5dc3dd0b 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -3358,7 +3358,8 @@ static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa, > update_guest_cr3 = false; > vmx_ept_load_pdptrs(vcpu); > } else { > - guest_cr3 = root_hpa | kvm_get_active_pcid(vcpu); > + guest_cr3 = root_hpa | kvm_get_active_pcid(vcpu) | > + kvm_get_active_cr3_lam_bits(vcpu); > } > > if (update_guest_cr3) > -- > 2.25.1 >