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 33083C0650F for ; Tue, 30 Jul 2019 11:22:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0E5B02087F for ; Tue, 30 Jul 2019 11:22:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729630AbfG3LW2 (ORCPT ); Tue, 30 Jul 2019 07:22:28 -0400 Received: from foss.arm.com ([217.140.110.172]:59468 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726870AbfG3LW2 (ORCPT ); Tue, 30 Jul 2019 07:22:28 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B350228; Tue, 30 Jul 2019 04:22:27 -0700 (PDT) Received: from [10.1.197.57] (e110467-lin.cambridge.arm.com [10.1.197.57]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B416E3F575; Tue, 30 Jul 2019 04:22:26 -0700 (PDT) Subject: Re: Failure to recreate virtual functions To: Lu Baolu , Vlad Buslov Cc: Joerg Roedel , Ran Rozenstein , "linux-kernel@vger.kernel.org" , "iommu@lists.linux-foundation.org" , Maor Gottlieb References: <838a00c4-d5bd-08db-e39c-5f00686858b5@linux.intel.com> From: Robin Murphy Message-ID: <6ece232e-3fe8-4bd9-cd4b-c8d90a106a30@arm.com> Date: Tue, 30 Jul 2019 12:22:25 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <838a00c4-d5bd-08db-e39c-5f00686858b5@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/07/2019 05:28, Lu Baolu wrote: > Hi, > > On 7/29/19 6:05 PM, Vlad Buslov wrote: >> On Sat 27 Jul 2019 at 05:15, Lu Baolu  wrote: >>> Hi Vilad, >>> >>> On 7/27/19 12:30 AM, Vlad Buslov wrote: >>>> Hi Lu Baolu, >>>> >>>> Our mlx5 driver fails to recreate VFs when cmdline includes >>>> "intel_iommu=on iommu=pt" after recent merge of patch set "iommu/vt-d: >>>> Delegate DMA domain to generic iommu". I've bisected the failure to >>>> patch b7297783c2bb ("iommu/vt-d: Remove duplicated code for device >>>> hotplug"). Here is the dmesg log for following case: enable switchdev >>>> mode, set number of VFs to 0, then set it back to any value >>>>> 0. >>>> [  223.525282] mlx5_core 0000:81:00.0: E-Switch: E-Switch enable >>>> SRIOV: nvfs(2) mode (1) >>>> [  223.562027] mlx5_core 0000:81:00.0: E-Switch: SRIOV enabled: >>>> active vports(3) >>>> [  223.663766] pci 0000:81:00.2: [15b3:101a] type 00 class 0x020000 >>>> [  223.663864] pci 0000:81:00.2: enabling Extended Tags >>>> [  223.665143] pci 0000:81:00.2: Adding to iommu group 52 >>>> [  223.665215] pci 0000:81:00.2: Using iommu direct mapping >>>> [  223.665771] mlx5_core 0000:81:00.2: enabling device (0000 -> 0002) >>>> [  223.665890] mlx5_core 0000:81:00.2: firmware version: 16.26.148 >>>> [  223.889908] mlx5_core 0000:81:00.2: Rate limit: 127 rates are >>>> supported, range: 0Mbps to 97656Mbps >>>> [  223.896438] mlx5_core 0000:81:00.2: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  223.896636] mlx5_core 0000:81:00.2: Assigned random MAC address >>>> 56:1f:95:e0:51:d6 >>>> [  224.012905] mlx5_core 0000:81:00.2 ens1f0v0: renamed from eth0 >>>> [  224.041651] pci 0000:81:00.3: [15b3:101a] type 00 class 0x020000 >>>> [  224.041711] pci 0000:81:00.3: enabling Extended Tags >>>> [  224.043660] pci 0000:81:00.3: Adding to iommu group 53 >>>> [  224.043738] pci 0000:81:00.3: Using iommu direct mapping >>>> [  224.044196] mlx5_core 0000:81:00.3: enabling device (0000 -> 0002) >>>> [  224.044298] mlx5_core 0000:81:00.3: firmware version: 16.26.148 >>>> [  224.268099] mlx5_core 0000:81:00.3: Rate limit: 127 rates are >>>> supported, range: 0Mbps to 97656Mbps >>>> [  224.274983] mlx5_core 0000:81:00.3: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  224.275195] mlx5_core 0000:81:00.3: Assigned random MAC address >>>> a6:1e:56:0a:d9:f2 >>>> [  224.388359] mlx5_core 0000:81:00.3 ens1f0v1: renamed from eth0 >>>> [  236.325027] mlx5_core 0000:81:00.0: E-Switch: disable SRIOV: >>>> active vports(3) mode(1) >>>> [  236.362766] mlx5_core 0000:81:00.0: E-Switch: E-Switch enable >>>> SRIOV: nvfs(2) mode (2) >>>> [  237.290066] mlx5_core 0000:81:00.0: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  237.350215] mlx5_core 0000:81:00.0: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  237.373052] mlx5_core 0000:81:00.0 ens1f0: renamed from eth0 >>>> [  237.390768] mlx5_core 0000:81:00.0: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  237.447846] ens1f0_0: renamed from eth0 >>>> [  237.460399] mlx5_core 0000:81:00.0: E-Switch: SRIOV enabled: >>>> active vports(3) >>>> [  237.526880] ens1f0_1: renamed from eth1 >>>> [  248.953873] pci 0000:81:00.2: Removing from iommu group 52 >>>> [  248.954114] pci 0000:81:00.3: Removing from iommu group 53 >>>> [  249.960570] mlx5_core 0000:81:00.0: E-Switch: disable SRIOV: >>>> active vports(3) mode(2) >>>> [  250.319135] mlx5_core 0000:81:00.0: MLX5E: StrdRq(1) RqSz(8) >>>> StrdSz(2048) RxCqeCmprss(0) >>>> [  250.559431] mlx5_core 0000:81:00.0 ens1f0: renamed from eth0 >>>> [  258.819162] mlx5_core 0000:81:00.0: E-Switch: E-Switch enable >>>> SRIOV: nvfs(2) mode (1) >>>> [  258.831625] mlx5_core 0000:81:00.0: E-Switch: SRIOV enabled: >>>> active vports(3) >>>> [  258.936160] pci 0000:81:00.2: [15b3:101a] type 00 class 0x020000 >>>> [  258.936258] pci 0000:81:00.2: enabling Extended Tags >>>> [  258.937438] pci 0000:81:00.2: Failed to add to iommu group 52: -16 >>> It seems that an EBUSY error returned from iommu_group_add_device(). Can >>> you please hack some debug messages in iommu_group_add_device() so that >>> we can know where the EBUSY returns? >>> >>> Best regards, >>> Baolu >> The error code is returned by __iommu_attach_device(). >> > > Thanks! > > It looks like the system has already a domain for specific pci bdf > device. Does this VF share the bdf with other devices? Or has been > previously created, and system failed to get chance to remove it? At a glance, it looks like it might be down to intel_iommu_remove_device() not calling dmar_remove_one_dev_info() like the old notifier did. If the group is getting torn down and recreated, but the driver still has a stale pointer to the old default domain cached, which dmar_insert_one_dev_info() finds and returns, that would seem to explain the observed behaviour. Robin.