From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760164AbcBYItM (ORCPT ); Thu, 25 Feb 2016 03:49:12 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39711 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758272AbcBYItL (ORCPT ); Thu, 25 Feb 2016 03:49:11 -0500 Subject: Re: [PATCH 09/12] KVM: MMU: coalesce zapping page after mmu_sync_children To: Xiao Guangrong , Takuya Yoshikawa , linux-kernel@vger.kernel.org, kvm@vger.kernel.org References: <1456319873-34182-1-git-send-email-pbonzini@redhat.com> <1456319873-34182-10-git-send-email-pbonzini@redhat.com> <56CE63D1.40009@lab.ntt.co.jp> <56CEAEA7.8080702@linux.intel.com> Cc: mtosatti@redhat.com From: Paolo Bonzini Message-ID: <56CEC003.1070402@redhat.com> Date: Thu, 25 Feb 2016 09:49:07 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.0 MIME-Version: 1.0 In-Reply-To: <56CEAEA7.8080702@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25/02/2016 08:35, Xiao Guangrong wrote: >> This may release the mmu_lock before committing the zapping. >> Is it safe? If so, we may want to see the reason in the changelog. > > It is unsafe indeed, please do not do it. Can you explain why? kvm_zap_obsolete_pages does the same. Paolo