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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 52496C47404 for ; Tue, 8 Oct 2019 02:30:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2F03421721 for ; Tue, 8 Oct 2019 02:30:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729772AbfJHCaM (ORCPT ); Mon, 7 Oct 2019 22:30:12 -0400 Received: from mga12.intel.com ([192.55.52.136]:50967 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729212AbfJHCaM (ORCPT ); Mon, 7 Oct 2019 22:30:12 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 07 Oct 2019 19:30:11 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.67,269,1566889200"; d="scan'208";a="192457101" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by fmsmga008.fm.intel.com with ESMTP; 07 Oct 2019 19:30:09 -0700 Cc: baolu.lu@linux.intel.com, David Woodhouse , Joerg Roedel , iommu@lists.linux-foundation.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, =?UTF-8?Q?Micha=c5=82_Wajdeczko?= Subject: Re: [RFC PATCH] iommu/vt-d: Fix IOMMU field not populated on device hot re-plug To: Janusz Krzysztofik References: <20190822142922.31526-1-janusz.krzysztofik@linux.intel.com> <52fbfac9-c879-4b45-dd74-fafe62c2432b@linux.intel.com> <2674326.ZPvzKFr69O@jkrzyszt-desk.ger.corp.intel.com> <7739498.9tyZrNxj5X@jkrzyszt-desk.ger.corp.intel.com> From: Lu Baolu Message-ID: <0131be21-0ae3-ac1e-6ee3-c256e3d2a38f@linux.intel.com> Date: Tue, 8 Oct 2019 10:27:57 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <7739498.9tyZrNxj5X@jkrzyszt-desk.ger.corp.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 10/1/19 11:01 PM, Janusz Krzysztofik wrote: > Hi Baolu, > > On Tuesday, September 3, 2019 9:41:23 AM CEST Janusz Krzysztofik wrote: >> Hi Baolu, >> >> On Tuesday, September 3, 2019 3:29:40 AM CEST Lu Baolu wrote: >>> Hi Janusz, >>> >>> On 9/2/19 4:37 PM, Janusz Krzysztofik wrote: >>>>> I am not saying that keeping data is not acceptable. I just want to >>>>> check whether there are any other solutions. >>>> Then reverting 458b7c8e0dde and applying this patch still resolves the >> issue >>>> for me. No errors appear when mappings are unmapped on device close after >> the >>>> device has been removed, and domain info preserved on device removal is >>>> successfully reused on device re-plug. >>> >>> This patch doesn't look good to me although I agree that keeping data is >>> acceptable. > > Any progress with that? Which mailing list should I watch for updates?\ We had a holiday last week. I will go ahead with reproducing it locally. Feel free to let me know if you have any new proposal. Best regards, Baolu > > Thanks, > Janusz > >>> It updates dev->archdata.iommu, but leaves the hardware >>> context/pasid table unchanged. This might cause problems somewhere. >>> >>>> >>>> Is there anything else I can do to help? >>> >>> Can you please tell me how to reproduce the problem? >> >> The most simple way to reproduce the issue, assuming there are no non-Intel >> graphics adapters installed, is to run the following shell commands: >> >> #!/bin/sh >> # load i915 module >> modprobe i915 >> # open an i915 device and keep it open in background >> cat /dev/dri/card0 >/dev/null & >> sleep 2 >> # simulate device unplug >> echo 1 >/sys/class/drm/card0/device/remove >> # make the background process close the device on exit >> kill $! >> >> Thanks, >> Janusz >> >> >>> Keeping the per >>> device domain info while device is unplugged is a bit dangerous because >>> info->dev might be a wild pointer. We need to work out a clean fix. >>> >>>> >>>> Thanks, >>>> Janusz >>>> >>> >>> Best regards, >>> Baolu >>> >> >> >> >> >> > > > > >