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=-2.2 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 B4377C43331 for ; Sat, 28 Mar 2020 21:55:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8422120732 for ; Sat, 28 Mar 2020 21:55:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727716AbgC1Vzw (ORCPT ); Sat, 28 Mar 2020 17:55:52 -0400 Received: from mga18.intel.com ([134.134.136.126]:18384 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727484AbgC1Vzv (ORCPT ); Sat, 28 Mar 2020 17:55:51 -0400 IronPort-SDR: jMwL8oLlxZWXVG7CfpkbPbLKtH2C2TbT2r6LgAp8S8NEX2RdDQhKhMYpn1cUoVwb4YDk8GWq0C Miq+cjtVJ+vg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 28 Mar 2020 14:55:51 -0700 IronPort-SDR: b6VcZ2A2a6MdrzFoVlo5Z9KXsPFNXA9DRFiw714UyVJBw/ATSfLQ9A9Mg03oADHPYV95I/J3lm sxnmRtzKaW/w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,317,1580803200"; d="scan'208";a="447822949" Received: from ssafrin-mobl.ger.corp.intel.com (HELO [10.255.229.125]) ([10.255.229.125]) by fmsmga005.fm.intel.com with ESMTP; 28 Mar 2020 14:55:50 -0700 Subject: Re: [PATCH v18 05/11] PCI/ERR: Remove service dependency in pcie_do_recovery() To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, ashok.raj@intel.com References: <20200328213241.GA127815@google.com> From: "Kuppuswamy, Sathyanarayanan" Message-ID: <110653ad-fd8f-8047-62de-dd9ce2cb9d5f@linux.intel.com> Date: Sat, 28 Mar 2020 14:55:50 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 MIME-Version: 1.0 In-Reply-To: <20200328213241.GA127815@google.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Hi Bjorn, On 3/28/20 2:32 PM, Bjorn Helgaas wrote: > On Sat, Mar 28, 2020 at 02:12:48PM -0700, Kuppuswamy, Sathyanarayanan wrote: >> On 3/23/20 5:26 PM, sathyanarayanan.kuppuswamy@linux.intel.com wrote: >>> From: Kuppuswamy Sathyanarayanan >>> >> >>> +void pcie_do_recovery(struct pci_dev *dev, >>> + enum pci_channel_state state, >>> + pci_ers_result_t (*reset_link)(struct pci_dev *pdev)) >>> { >>> pci_ers_result_t status = PCI_ERS_RESULT_CAN_RECOVER; >>> struct pci_bus *bus; >>> @@ -206,9 +165,12 @@ void pcie_do_recovery(struct pci_dev *dev, enum pci_channel_state state, >>> pci_dbg(dev, "broadcast error_detected message\n"); >>> if (state == pci_channel_io_frozen) { >>> pci_walk_bus(bus, report_frozen_detected, &status); >>> - status = reset_link(dev, service); >>> - if if (reset_link) >> status = reset_link(dev);(status == PCI_ERS_RESULT_DISCONNECT >>> + status = reset_link(dev); >> Above line needs to be replaced as below. Since there is a >> possibility reset_link can NULL (eventhough currently its >> not true). >> if (reset_link) >> status = reset_link(dev); >> Shall I submit another version to add above fix on top of >> our pci/edr branch ? > > No, I can squash that in if needed. > > But I don't actually think we *do* need it. All the callers supply a > valid reset_link function pointer, and if somebody changes or adds a > new one that doesn't, I'd rather take the null pointer exception and > find out about it than silently ignore it. But the documentation says "If reset_link is not NULL, recovery function will use it to reset the link." It considers NULL as a possible case. So I think its better to allow that case with a pci_warn() message. > > Bjorn >