Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933314AbbLWLdO (ORCPT ); Wed, 23 Dec 2015 06:33:14 -0500 Received: from mga01.intel.com ([192.55.52.88]:27842 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933060AbbLWLdI (ORCPT ); Wed, 23 Dec 2015 06:33:08 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.20,468,1444719600"; d="scan'208";a="877401190" From: Xiao Guangrong To: pbonzini@redhat.com Cc: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kai.huang@linux.intel.com, jike.song@intel.com, Xiao Guangrong Subject: [PATCH v2 08/11] KVM: MMU: use page track for non-leaf shadow pages Date: Wed, 23 Dec 2015 19:25:51 +0800 Message-Id: <1450869954-30273-9-git-send-email-guangrong.xiao@linux.intel.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1450869954-30273-1-git-send-email-guangrong.xiao@linux.intel.com> References: <1450869954-30273-1-git-send-email-guangrong.xiao@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2637 Lines: 78 non-leaf shadow pages are always write protected, it can be the user of page track Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index b23f9fc..5a2ca73 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -806,11 +806,17 @@ static void account_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) struct kvm_memory_slot *slot; gfn_t gfn; + kvm->arch.indirect_shadow_pages++; gfn = sp->gfn; slots = kvm_memslots_for_spte_role(kvm, sp->role); slot = __gfn_to_memslot(slots, gfn); + + /* the non-leaf shadow pages are keeping readonly. */ + if (sp->role.level > PT_PAGE_TABLE_LEVEL) + return kvm_slot_page_track_add_page_nolock(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE); + kvm_mmu_gfn_disallow_lpage(slot, gfn); - kvm->arch.indirect_shadow_pages++; } static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) @@ -819,11 +825,15 @@ static void unaccount_shadowed(struct kvm *kvm, struct kvm_mmu_page *sp) struct kvm_memory_slot *slot; gfn_t gfn; + kvm->arch.indirect_shadow_pages--; gfn = sp->gfn; slots = kvm_memslots_for_spte_role(kvm, sp->role); slot = __gfn_to_memslot(slots, gfn); + if (sp->role.level > PT_PAGE_TABLE_LEVEL) + return kvm_slot_page_track_remove_page_nolock(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE); + kvm_mmu_gfn_allow_lpage(slot, gfn); - kvm->arch.indirect_shadow_pages--; } static bool __mmu_gfn_lpage_is_disallowed(gfn_t gfn, int level, @@ -2140,12 +2150,18 @@ static struct kvm_mmu_page *kvm_mmu_get_page(struct kvm_vcpu *vcpu, hlist_add_head(&sp->hash_link, &vcpu->kvm->arch.mmu_page_hash[kvm_page_table_hashfn(gfn)]); if (!direct) { - if (rmap_write_protect(vcpu, gfn)) + /* + * we should do write protection before syncing pages + * otherwise the content of the synced shadow page may + * be inconsistent with guest page table. + */ + account_shadowed(vcpu->kvm, sp); + + if (level == PT_PAGE_TABLE_LEVEL && + rmap_write_protect(vcpu, gfn)) kvm_flush_remote_tlbs(vcpu->kvm); if (level > PT_PAGE_TABLE_LEVEL && need_sync) kvm_sync_pages(vcpu, gfn); - - account_shadowed(vcpu->kvm, sp); } sp->mmu_valid_gen = vcpu->kvm->arch.mmu_valid_gen; init_shadow_page_table(sp); -- 1.8.3.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/