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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 26177C28CF8 for ; Sat, 13 Oct 2018 16:29:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE8D020659 for ; Sat, 13 Oct 2018 16:29:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DE8D020659 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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 S1726861AbeJNAHC (ORCPT ); Sat, 13 Oct 2018 20:07:02 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51414 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726129AbeJNAHC (ORCPT ); Sat, 13 Oct 2018 20:07:02 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C70B981DE1; Sat, 13 Oct 2018 16:29:14 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 394E4607C4; Sat, 13 Oct 2018 16:29:14 +0000 (UTC) Received: from zmail21.collab.prod.int.phx2.redhat.com (zmail21.collab.prod.int.phx2.redhat.com [10.5.83.24]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id A623D180053A; Sat, 13 Oct 2018 16:29:13 +0000 (UTC) Date: Sat, 13 Oct 2018 12:29:12 -0400 (EDT) From: Pankaj Gupta To: Dan Williams Cc: Kevin Wolf , Jan Kara , Xiao Guangrong , KVM list , Rik van Riel , linux-nvdimm , David Hildenbrand , Linux Kernel Mailing List , Dave Jiang , Qemu Developers , Christoph Hellwig , Vishal L Verma , Igor Mammedov , "Michael S. Tsirkin" , Stefan Hajnoczi , zwisler@kernel.org, lcapitulino@redhat.com, Paolo Bonzini , Nitesh Narayan Lal Message-ID: <2107404743.20781403.1539448152851.JavaMail.zimbra@redhat.com> In-Reply-To: References: <20181013050021.11962-1-pagupta@redhat.com> Subject: Re: [Qemu-devel] [PATCH v2 0/2] kvm "fake DAX" device MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.116.15, 10.4.195.9] Thread-Topic: kvm "fake DAX" device Thread-Index: +S5hvCT+X5OpmacPj4Q8TC96GIS4Ug== X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Sat, 13 Oct 2018 16:29:15 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > > > This patch series has implementation for "fake DAX". > > "fake DAX" is fake persistent memory(nvdimm) in guest > > which allows to bypass the guest page cache. This also > > implements a VIRTIO based asynchronous flush mechanism. > > Can we stop calling this 'fake DAX', because it isn't 'DAX' and it's > starting to confuse people. This enabling is effectively a > host-page-cache-passthrough mechanism not DAX. Let's call the whole > approach virtio-pmem, and leave DAX out of the name to hopefully > prevent people from wondering why some DAX features are disabled with > this driver. For example MAP_SYNC is not compatible with this > approach. Sure. I got your point. I will use "virtio-pmem" in future. > > Additional enabling is need to disable MAP_SYNC in the presence of a > virtio-pmem device. See the rough proposal here: > > https://lkml.org/lkml/2018/4/25/756 Yes, I will handle disabling of MAP_SYNC for this use-case. Thanks, Pankaj