Received: by 2002:a25:683:0:0:0:0:0 with SMTP id 125csp2005828ybg; Fri, 5 Jun 2020 03:11:13 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwlTmYKKAYxmMiEyXI8iDcunOHbK654KEycVpl27K0OE4gj6bskPRkqN6A2YVEdPZsAQUB+ X-Received: by 2002:a17:906:1e95:: with SMTP id e21mr8217679ejj.240.1591351873108; Fri, 05 Jun 2020 03:11:13 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1591351873; cv=none; d=google.com; s=arc-20160816; b=Q2DC1x3Rj9t1qDR9zkjw+twyFq+dq6eZRwJnm+6WGa9CuVaqZLIPrQcjy8WB0E1jeO F2rYheHdJ+4bbfomJ+lHiHwvvcyqGhQo7qnmWGqx12Tr83ua6rDoJ4x7qvzxfg0+ymgj AgEYRzgU+cUKm3y338eGyEqSjsApfnzCv8Hc+UvvwJPSY01Mwb8msf2XCl50mcqHutQY RwWYfn7xFzz4RFplgedWe1RPr0GyJEleYFNHq6Oc+AqQUkl8Epoc4M3mhWsRw6dP5b3g aFknAtC9fL0Qt3M2MYDaiaftRM1IrtpzsBAr03g8IctpNcNuzxBsJw6Lfrf1KnlQ+01p BJHg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:in-reply-to :mime-version:user-agent:date:message-id:from:references:cc:to :subject; bh=2od5KuejwlWXAbRzyckPO+Xdxj4Z6lsytwRk92gGkkc=; b=gzv1T9X4Y02x336Bq7nigrmkosTGrujksQ+bh3/RKZEn5yQsqwMsvO+cWgSIOfEgfv mpFjw5xUP5w29q23Ja45aoUFbyPZnYOwe1TpHdVfIkk/iqJAz7bXiqd8Zpqp9C3Txzj5 qePcR5z5Q1P5/pBuHFzslfAiQntR+lQy2tN99FVVWTzLQKk1xUHLQW4tZ0XrlpZ7IkMZ eBAOzTBmAf7M8WyxP6VXOij3LhznGnYeiKTzcnMDOgafS6HO9yiQ0SYj+h9LIs5ZofOX TFGCzG7V5VXFlQ3Re3QgPIvc8fsQ0d4UYbOcUuLPfz/XKm74NM3dHrC18vIBE4QQ/zZa FeXw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id u23si3178871eds.526.2020.06.05.03.10.50; Fri, 05 Jun 2020 03:11:13 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=alibaba.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726245AbgFEKJE (ORCPT + 99 others); Fri, 5 Jun 2020 06:09:04 -0400 Received: from out30-44.freemail.mail.aliyun.com ([115.124.30.44]:45717 "EHLO out30-44.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725926AbgFEKJD (ORCPT ); Fri, 5 Jun 2020 06:09:03 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R441e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01355;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=39;SR=0;TI=SMTPD_---0U-dqblm_1591351735; Received: from IT-FVFX43SYHV2H.local(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0U-dqblm_1591351735) by smtp.aliyun-inc.com(127.0.0.1); Fri, 05 Jun 2020 18:08:56 +0800 Subject: Re: [PATCH RFC v4 00/13] virtio-mem: paravirtualized memory To: David Hildenbrand , linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, Michal Hocko , Andrew Morton , "Michael S . Tsirkin" , Sebastien Boeuf , Samuel Ortiz , Robert Bradford , Luiz Capitulino , Alexander Duyck , Alexander Potapenko , Alexander Viro , Anshuman Khandual , Anthony Yznaga , Dan Williams , Dave Young , Igor Mammedov , Jason Wang , Johannes Weiner , Juergen Gross , Konrad Rzeszutek Wilk , Len Brown , Mel Gorman , Michal Hocko , Mike Rapoport , Oscar Salvador , Oscar Salvador , Pavel Tatashin , Pavel Tatashin , Pingfan Liu , Qian Cai , "Rafael J. Wysocki" , Stefan Hajnoczi , Vlastimil Babka , Wei Yang References: <20191212171137.13872-1-david@redhat.com> <9acc5d04-c8e9-ef53-85e4-709030997ca6@redhat.com> <1cfa9edb-47ea-1495-4e28-4cf391eab44c@linux.alibaba.com> <6b4724bf-84b5-9880-5464-1908425d106d@redhat.com> From: Alex Shi Message-ID: <741e7d4b-4433-98fc-f849-cbb460d61a41@linux.alibaba.com> Date: Fri, 5 Jun 2020 18:08:55 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <6b4724bf-84b5-9880-5464-1908425d106d@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2020/6/5 下午5:36, David Hildenbrand 写道: > I guess I know what's happening here. In case we only have DMA memory > when booting, we don't reserve swiotlb buffers. Once we hotplug memory > and online ZONE_NORMAL, we don't have any swiotlb DMA bounce buffers to > map such PFNs (total 0 (slots), used 0 (slots)). > > Can you try with "swiotlb=force" on the kernel cmdline? Yes, it works fine with this cmdline. problems gone,