From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: Re: [PATCH v3 1/6] KVM: MMU: fix forgot flush tlbs on sync_page path Date: Fri, 26 Nov 2010 09:37:12 +0800 Message-ID: <4CEF0F48.8000202@cn.fujitsu.com> References: <4CE63CF4.80502@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , KVM , LKML To: Avi Kivity Return-path: Received: from cn.fujitsu.com ([222.73.24.84]:62886 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752470Ab0KZBcd (ORCPT ); Thu, 25 Nov 2010 20:32:33 -0500 In-Reply-To: <4CE63CF4.80502@cn.fujitsu.com> Sender: kvm-owner@vger.kernel.org List-ID: Hi Avi, Marcelo, What do you think of this patchset? Could you give me some comments please? Thanks! On 11/19/2010 05:01 PM, Xiao Guangrong wrote: > We should flush all tlbs after drop spte on sync_page path since: > > Quote from Avi: > | sync_page > | drop_spte > | kvm_mmu_notifier_invalidate_page > | kvm_unmap_rmapp > | spte doesn't exist -> no flush > | page is freed > | guest can write into freed page? > > Signed-off-by: Xiao Guangrong > --- > arch/x86/kvm/paging_tmpl.h | 1 + > 1 files changed, 1 insertions(+), 0 deletions(-) > > diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h > index 590bf12..ca0e5e8 100644 > --- a/arch/x86/kvm/paging_tmpl.h > +++ b/arch/x86/kvm/paging_tmpl.h > @@ -786,6 +786,7 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, > else > nonpresent = shadow_notrap_nonpresent_pte; > drop_spte(vcpu->kvm, &sp->spt[i], nonpresent); > + kvm_flush_remote_tlbs(vcpu->kvm); > continue; > } >