From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=0.2 required=3.0 tests=DATE_IN_FUTURE_03_06, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D48A3C433F5 for ; Thu, 30 Aug 2018 10:44:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A00C2073D for ; Thu, 30 Aug 2018 10:44:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9A00C2073D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728492AbeH3Ops (ORCPT ); Thu, 30 Aug 2018 10:45:48 -0400 Received: from mga07.intel.com ([134.134.136.100]:41906 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728318AbeH3Ops (ORCPT ); Thu, 30 Aug 2018 10:45:48 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 30 Aug 2018 03:44:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,306,1531810800"; d="scan'208";a="84639912" Received: from linux.intel.com ([10.54.29.200]) by fmsmga004.fm.intel.com with ESMTP; 30 Aug 2018 03:44:16 -0700 Received: from tiger-server (dazhang1-ssd.sh.intel.com [10.239.48.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id 3A091580224; Thu, 30 Aug 2018 03:44:14 -0700 (PDT) Date: Fri, 31 Aug 2018 03:23:13 +0800 From: Yi Zhang To: Pankaj Gupta Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, pbonzini@redhat.com, dan j williams , dave jiang , yu c zhang , david@redhat.com, jack@suse.cz, hch@lst.de, linux-mm@kvack.org, rkrcmar@redhat.com, jglisse@redhat.com, yi z zhang Subject: Re: [PATCH V4 4/4] kvm: add a check if pfn is from NVDIMM pmem. Message-ID: <20180830192312.GA84758@tiger-server> Mail-Followup-To: Pankaj Gupta , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, pbonzini@redhat.com, dan j williams , dave jiang , yu c zhang , david@redhat.com, jack@suse.cz, hch@lst.de, linux-mm@kvack.org, rkrcmar@redhat.com, jglisse@redhat.com, yi z zhang References: <380594559.7598107.1535537748154.JavaMail.zimbra@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <380594559.7598107.1535537748154.JavaMail.zimbra@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-08-29 at 06:15:48 -0400, Pankaj Gupta wrote: > > > > > For device specific memory space, when we move these area of pfn to > > memory zone, we will set the page reserved flag at that time, some of > > these reserved for device mmio, and some of these are not, such as > > NVDIMM pmem. > > > > Now, we map these dev_dax or fs_dax pages to kvm for DIMM/NVDIMM > > backend, since these pages are reserved, the check of > > kvm_is_reserved_pfn() misconceives those pages as MMIO. Therefor, we > > introduce 2 page map types, MEMORY_DEVICE_FS_DAX/MEMORY_DEVICE_DEV_DAX, > > to identify these pages are from NVDIMM pmem and let kvm treat these > > as normal pages. > > > > Without this patch, many operations will be missed due to this > > mistreatment to pmem pages, for example, a page may not have chance to > > be unpinned for KVM guest(in kvm_release_pfn_clean), not able to be > > marked as dirty/accessed(in kvm_set_pfn_dirty/accessed) etc. > > > > Signed-off-by: Zhang Yi > > --- > > virt/kvm/kvm_main.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > > > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > > index c44c406..969b6ca 100644 > > --- a/virt/kvm/kvm_main.c > > +++ b/virt/kvm/kvm_main.c > > @@ -147,8 +147,12 @@ __weak void > > kvm_arch_mmu_notifier_invalidate_range(struct kvm *kvm, > > > > bool kvm_is_reserved_pfn(kvm_pfn_t pfn) > > { > > - if (pfn_valid(pfn)) > > - return PageReserved(pfn_to_page(pfn)); > > + struct page *page; > > + > > + if (pfn_valid(pfn)) { > > + page = pfn_to_page(pfn); > > + return PageReserved(page) && !is_dax_page(page); > > + } > > > > return true; > > } > > Acked-by: Pankaj Gupta Thanks for your kindly review, Pankaj, as all the patch [1,2,3,4]/4 got the reviewed[acked]-by, can we Queue this by now? > > > -- > > 2.7.4 > > > >