From patchwork Fri Jun 25 12:05:24 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 108028 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.4/8.14.3) with ESMTP id o5PC9nPR006790 for ; Fri, 25 Jun 2010 12:09:49 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752444Ab0FYMJR (ORCPT ); Fri, 25 Jun 2010 08:09:17 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:62176 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751967Ab0FYMJQ (ORCPT ); Fri, 25 Jun 2010 08:09:16 -0400 Received: from tang.cn.fujitsu.com (tang.cn.fujitsu.com [10.167.250.3]) by song.cn.fujitsu.com (Postfix) with ESMTP id 263AE17011C; Fri, 25 Jun 2010 20:09:10 +0800 (CST) Received: from fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id o5PC6ZOA011816; Fri, 25 Jun 2010 20:06:35 +0800 Received: from [10.167.141.99] (unknown [10.167.141.99]) by fnst.cn.fujitsu.com (Postfix) with ESMTPA id 2C28D10C005; Fri, 25 Jun 2010 20:09:05 +0800 (CST) Message-ID: <4C249B84.4080703@cn.fujitsu.com> Date: Fri, 25 Jun 2010 20:05:24 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM list Subject: [PATCH v2 1/10] KVM: MMU: fix writable sync sp mapping Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 25 Jun 2010 12:09:49 +0000 (UTC) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 045a0f9..556a798 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1810,11 +1810,14 @@ static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn, bool need_unsync = false; for_each_gfn_indirect_valid_sp(vcpu->kvm, s, gfn, node) { + if (!can_unsync) + return 1; + if (s->role.level != PT_PAGE_TABLE_LEVEL) return 1; if (!need_unsync && !s->unsync) { - if (!can_unsync || !oos_shadow) + if (!oos_shadow) return 1; need_unsync = true; } @@ -1877,15 +1880,6 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, if (!tdp_enabled && !(pte_access & ACC_WRITE_MASK)) spte &= ~PT_USER_MASK; - /* - * Optimization: for pte sync, if spte was writable the hash - * lookup is unnecessary (and expensive). Write protection - * is responsibility of mmu_get_page / kvm_sync_page. - * Same reasoning can be applied to dirty page accounting. - */ - if (!can_unsync && is_writable_pte(*sptep)) - goto set_pte; - if (mmu_need_write_protect(vcpu, gfn, can_unsync)) { pgprintk("%s: found shadow page for %lx, marking ro\n", __func__, gfn);