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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 1743EC43381 for ; Mon, 1 Apr 2019 17:37:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EA17D20830 for ; Mon, 1 Apr 2019 17:37:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388212AbfDARhi (ORCPT ); Mon, 1 Apr 2019 13:37:38 -0400 Received: from mga17.intel.com ([192.55.52.151]:27929 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388200AbfDARhf (ORCPT ); Mon, 1 Apr 2019 13:37:35 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 01 Apr 2019 10:37:26 -0700 X-IronPort-AV: E=Sophos;i="5.60,297,1549958400"; d="scan'208";a="130525188" Received: from unknown (HELO [10.232.112.189]) ([10.232.112.189]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/AES128-SHA; 01 Apr 2019 10:37:25 -0700 Subject: Re: [PATCH AUTOSEL 4.19 28/57] nvme-pci: fix conflicting p2p resource adds To: Sasha Levin , linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Keith Busch , Jens Axboe , Christoph Hellwig , linux-nvme@lists.infradead.org References: <20190330012854.32212-1-sashal@kernel.org> <20190330012854.32212-28-sashal@kernel.org> From: "Heitke, Kenneth" Message-ID: <2f3dacd3-7a3d-2773-013d-8f7d5e5cfab5@intel.com> Date: Mon, 1 Apr 2019 11:36:38 -0600 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <20190330012854.32212-28-sashal@kernel.org> 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 On 3/29/2019 7:28 PM, Sasha Levin wrote: > From: Keith Busch > > [ Upstream commit 9fe5c59ff6a1e5e26a39b75489a1420e7eaaf0b1 ] > > The nvme pci driver had been adding its CMB resource to the P2P DMA > subsystem everytime on on a controller reset. This results in the > following warning: > > ------------[ cut here ]------------ > nvme 0000:00:03.0: Conflicting mapping in same section > WARNING: CPU: 7 PID: 81 at kernel/memremap.c:155 devm_memremap_pages+0xa6/0x380 > ... > Call Trace: > pci_p2pdma_add_resource+0x153/0x370 > nvme_reset_work+0x28c/0x17b1 [nvme] > ? add_timer+0x107/0x1e0 > ? dequeue_entity+0x81/0x660 > ? dequeue_entity+0x3b0/0x660 > ? pick_next_task_fair+0xaf/0x610 > ? __switch_to+0xbc/0x410 > process_one_work+0x1cf/0x350 > worker_thread+0x215/0x3d0 > ? process_one_work+0x350/0x350 > kthread+0x107/0x120 > ? kthread_park+0x80/0x80 > ret_from_fork+0x1f/0x30 > ---[ end trace f7ea76ac6ee72727 ]--- > nvme nvme0: failed to register the CMB > > This patch fixes this by registering the CMB with P2P only once. > > Signed-off-by: Keith Busch > Reviewed-by: Logan Gunthorpe > Signed-off-by: Christoph Hellwig > Signed-off-by: Jens Axboe > Signed-off-by: Sasha Levin > --- > drivers/nvme/host/pci.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c > index 7b9ef8e734e7..dca87cb485e9 100644 > --- a/drivers/nvme/host/pci.c > +++ b/drivers/nvme/host/pci.c > @@ -1649,6 +1649,9 @@ static void nvme_map_cmb(struct nvme_dev *dev) > struct pci_dev *pdev = to_pci_dev(dev->dev); > int bar; > > + if (dev->cmb_size) > + return; > + > dev->cmbsz = readl(dev->bar + NVME_REG_CMBSZ); > if (!dev->cmbsz) > return; > @@ -2133,7 +2136,6 @@ static void nvme_pci_disable(struct nvme_dev *dev) > { > struct pci_dev *pdev = to_pci_dev(dev->dev); > > - nvme_release_cmb(dev); > pci_free_irq_vectors(pdev); > > if (pci_is_enabled(pdev)) { > @@ -2585,6 +2587,7 @@ static void nvme_remove(struct pci_dev *pdev) > nvme_stop_ctrl(&dev->ctrl); > nvme_remove_namespaces(&dev->ctrl); > nvme_dev_disable(dev, true); > + nvme_release_cmb(dev); > nvme_free_host_mem(dev); > nvme_dev_remove_admin(dev); > nvme_free_queues(dev, 0); There is no P2P support in the 4.19 kernel so I'm not sure this change is necessary. I would also worry that it might break things if the BARs need to be remapped after a controller reset. >