From patchwork Sat Oct 10 15:16:54 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hedi Berriche X-Patchwork-Id: 11830347 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 09AAD1592 for ; Sat, 10 Oct 2020 22:52:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D31D82083B for ; Sat, 10 Oct 2020 22:51:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=hpe.com header.i=@hpe.com header.b="NCoBl+Kc" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730496AbgJJWvg (ORCPT ); Sat, 10 Oct 2020 18:51:36 -0400 Received: from mx0b-002e3701.pphosted.com ([148.163.143.35]:61168 "EHLO mx0b-002e3701.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731456AbgJJTXQ (ORCPT ); Sat, 10 Oct 2020 15:23:16 -0400 Received: from pps.filterd (m0148664.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 09AFGhlb023141; Sat, 10 Oct 2020 15:17:25 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hpe.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pps0720; bh=wSRn6DStJQfrwSTDj+DfXKvQUD8C1Q/aQBRYMzWuv7I=; b=NCoBl+Kc3r3M1kI5Tf+OiPMK2jerC073U7v7rK6SsaWfT36y1gNZJqjvMlGl+cdXdKnN 5ZKDV8NlN8h+Pp2qccw4fqURlBTC9M86I0E2D6b+kgpMEfgCwmZNoyxpv+u2oyphPvHN DOOqhkN9tiUmXvt0WEkIjC5FJcr+4wHjw4q7pPqQl3FGWj7lkzDSIaTDZA3P8wkQ5WdJ HNSAZisK6UzL/6eqyhUu0PV8c0Dyfihy3LNXqTZM5EvSBSEhv4BWatFkwZb6hglQNagF knTtOpwt0zRpDRKoPRSbvweK7AVqOsNg8UJ3Ox/KOnamzuPo4pPtXnn57iCEgZgHQF8A Pg== Received: from g4t3426.houston.hpe.com (g4t3426.houston.hpe.com [15.241.140.75]) by mx0b-002e3701.pphosted.com with ESMTP id 34342ujnvs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 10 Oct 2020 15:17:25 +0000 Received: from g4t3433.houston.hpecorp.net (g4t3433.houston.hpecorp.net [16.208.49.245]) by g4t3426.houston.hpe.com (Postfix) with ESMTP id 175FF61; Sat, 10 Oct 2020 15:17:25 +0000 (UTC) Received: from sarge.linuxathome.me (unknown [16.29.167.198]) by g4t3433.houston.hpecorp.net (Postfix) with ESMTP id 4A78D45; Sat, 10 Oct 2020 15:17:23 +0000 (UTC) From: Hedi Berriche To: sathyanarayanan.kuppuswamy@linux.intel.com Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Hedi Berriche , Russ Anderson , Bjorn Helgaas , Ashok Raj , Joerg Roedel , stable@kernel.org Subject: [PATCH v3 1/1] PCI/ERR: don't clobber status after reset_link() Date: Sat, 10 Oct 2020 16:16:54 +0100 Message-Id: <20201010151654.2707914-2-hedi.berriche@hpe.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201010151654.2707914-1-hedi.berriche@hpe.com> References: <20201010151654.2707914-1-hedi.berriche@hpe.com> MIME-Version: 1.0 X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.235,18.0.687 definitions=2020-10-10_07:2020-10-09,2020-10-10 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 mlxlogscore=999 clxscore=1015 mlxscore=0 lowpriorityscore=0 adultscore=0 malwarescore=0 suspectscore=1 spamscore=0 bulkscore=0 priorityscore=1501 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010100143 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Commit 6d2c89441571 ("PCI/ERR: Update error status after reset_link()") broke pcie_do_recovery(): updating status after reset_link() has the ill side effect of causing recovery to fail if the error status is PCI_ERS_RESULT_CAN_RECOVER or PCI_ERS_RESULT_NEED_RESET as the following code will *never* run in the case of a successful reset_link() 177 if (status == PCI_ERS_RESULT_CAN_RECOVER) { ... 181 } 183 if (status == PCI_ERS_RESULT_NEED_RESET) { ... 192 } For instance in the case of PCI_ERS_RESULT_NEED_RESET we end up not calling ->slot_reset() (because we skip report_slot_reset()) thus breaking driver (re)initialisation. Don't clobber status with the return value of reset_link(); set status to PCI_ERS_RESULT_RECOVERED, in case of successful link reset, if and only if the initial value of error status is PCI_ERS_RESULT_DISCONNECT or PCI_ERS_RESULT_NO_AER_DRIVER. Fixes: 6d2c89441571 ("PCI/ERR: Update error status after reset_link()") Signed-off-by: Hedi Berriche Cc: Russ Anderson Cc: Kuppuswamy Sathyanarayanan Cc: Bjorn Helgaas Cc: Ashok Raj Cc: Joerg Roedel Cc: stable@kernel.org # v5.7+ --- drivers/pci/pcie/err.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index c543f419d8f9..2730826cfd8a 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -165,10 +165,13 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, 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); - if (status != PCI_ERS_RESULT_RECOVERED) { + if (reset_link(dev) != PCI_ERS_RESULT_RECOVERED) { pci_warn(dev, "link reset failed\n"); goto failed; + } else { + if (status == PCI_ERS_RESULT_DISCONNECT || + status == PCI_ERS_RESULT_NO_AER_DRIVER) + status = PCI_ERS_RESULT_RECOVERED; } } else { pci_walk_bus(bus, report_normal_detected, &status);