From patchwork Tue Jul 10 17:04:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhang, Yi" X-Patchwork-Id: 10516519 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A8635600CA for ; Tue, 10 Jul 2018 08:26:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 97E0628B68 for ; Tue, 10 Jul 2018 08:26:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8BB3828C6F; Tue, 10 Jul 2018 08:26:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.0 required=2.0 tests=BAYES_00, DATE_IN_FUTURE_06_12, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E773B28B68 for ; Tue, 10 Jul 2018 08:26:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933182AbeGJIZv (ORCPT ); Tue, 10 Jul 2018 04:25:51 -0400 Received: from mga18.intel.com ([134.134.136.126]:3271 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212AbeGJIZt (ORCPT ); Tue, 10 Jul 2018 04:25:49 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jul 2018 01:25:49 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,333,1526367600"; d="scan'208";a="70108889" Received: from linux.intel.com ([10.54.29.200]) by fmsmga004.fm.intel.com with ESMTP; 10 Jul 2018 01:25:46 -0700 Received: from dazhang1-ssd.sh.intel.com (unknown [10.239.48.78]) by linux.intel.com (Postfix) with ESMTP id 966B1580388; Tue, 10 Jul 2018 01:25:44 -0700 (PDT) From: Zhang Yi To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, pbonzini@redhat.com, dan.j.williams@intel.com, jack@suse.cz, hch@lst.de, yu.c.zhang@intel.com Cc: linux-mm@kvack.org, rkrcmar@redhat.com, yi.z.zhang@intel.com, Zhang Yi Subject: [PATCH V2 4/4] kvm: add a check if pfn is from NVDIMM pmem. Date: Wed, 11 Jul 2018 01:04:08 +0800 Message-Id: X-Mailer: git-send-email 2.7.4 In-Reply-To: References: Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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 indentify 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 afb2e6e..77e6ba8 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -142,8 +142,12 @@ __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; }