From patchwork Tue Dec 18 07:26:47 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takuya Yoshikawa X-Patchwork-Id: 1890601 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 3494EDF23A for ; Tue, 18 Dec 2012 07:26:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753997Ab2LRH0R (ORCPT ); Tue, 18 Dec 2012 02:26:17 -0500 Received: from tama500.ecl.ntt.co.jp ([129.60.39.148]:53432 "EHLO tama500.ecl.ntt.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751259Ab2LRH0R (ORCPT ); Tue, 18 Dec 2012 02:26:17 -0500 Received: from mfs6.rdh.ecl.ntt.co.jp (mfs6.rdh.ecl.ntt.co.jp [129.60.39.149]) by tama500.ecl.ntt.co.jp (8.13.8/8.13.8) with ESMTP id qBI7QEoQ000429; Tue, 18 Dec 2012 16:26:14 +0900 Received: from mfs6.rdh.ecl.ntt.co.jp (localhost.localdomain [127.0.0.1]) by mfs6.rdh.ecl.ntt.co.jp (Postfix) with ESMTP id 7753EE0141; Tue, 18 Dec 2012 16:26:14 +0900 (JST) Received: from imail2.m.ecl.ntt.co.jp (imail2.m.ecl.ntt.co.jp [129.60.5.247]) by mfs6.rdh.ecl.ntt.co.jp (Postfix) with ESMTP id 62298E0140; Tue, 18 Dec 2012 16:26:14 +0900 (JST) Received: from yshpad ([129.60.241.236]) by imail2.m.ecl.ntt.co.jp (8.13.8/8.13.8) with SMTP id qBI7QEce003160; Tue, 18 Dec 2012 16:26:14 +0900 Date: Tue, 18 Dec 2012 16:26:47 +0900 From: Takuya Yoshikawa To: mtosatti@redhat.com, gleb@redhat.com Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/7] KVM: Write protect the updated slot only when we start dirty logging Message-Id: <20121218162647.009f468e.yoshikawa_takuya_b1@lab.ntt.co.jp> In-Reply-To: <20121218162558.65a8bfd3.yoshikawa_takuya_b1@lab.ntt.co.jp> References: <20121218162558.65a8bfd3.yoshikawa_takuya_b1@lab.ntt.co.jp> X-Mailer: Sylpheed 3.1.0 (GTK+ 2.24.4; x86_64-pc-linux-gnu) Mime-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This is needed to make kvm_mmu_slot_remove_write_access() rmap based: otherwise we may end up using invalid rmap's. Signed-off-by: Takuya Yoshikawa --- arch/x86/kvm/x86.c | 9 ++++++++- virt/kvm/kvm_main.c | 1 - 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 1c9c834..9451efa 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6897,7 +6897,14 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, spin_lock(&kvm->mmu_lock); if (nr_mmu_pages) kvm_mmu_change_mmu_pages(kvm, nr_mmu_pages); - kvm_mmu_slot_remove_write_access(kvm, mem->slot); + /* + * Write protect all pages for dirty logging. + * Existing largepage mappings are destroyed here and new ones will + * not be created until the end of the logging. + */ + if ((mem->flags & KVM_MEM_LOG_DIRTY_PAGES) && + !(old.flags & KVM_MEM_LOG_DIRTY_PAGES)) + kvm_mmu_slot_remove_write_access(kvm, mem->slot); spin_unlock(&kvm->mmu_lock); /* * If memory slot is created, or moved, we need to clear all diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index bd31096..0ef5daa 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -805,7 +805,6 @@ int __kvm_set_memory_region(struct kvm *kvm, if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) { if (kvm_create_dirty_bitmap(&new) < 0) goto out_free; - /* destroy any largepage mappings for dirty tracking */ } if (!npages || base_gfn != old.base_gfn) {