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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable 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 7CA8DC4CED1 for ; Sat, 5 Oct 2019 02:19:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 532C720873 for ; Sat, 5 Oct 2019 02:19:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726654AbfJECTC (ORCPT ); Fri, 4 Oct 2019 22:19:02 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:48686 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725907AbfJECTB (ORCPT ); Fri, 4 Oct 2019 22:19:01 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x952GZWv090570; Fri, 4 Oct 2019 22:18:56 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vehga91t9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Oct 2019 22:18:56 -0400 Received: from m0098413.ppops.net (m0098413.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.27/8.16.0.27) with SMTP id x952GYQK090530; Fri, 4 Oct 2019 22:18:56 -0400 Received: from ppma03dal.us.ibm.com (b.bd.3ea9.ip4.static.sl-reverse.com [169.62.189.11]) by mx0b-001b2d01.pphosted.com with ESMTP id 2vehga91sv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 04 Oct 2019 22:18:55 -0400 Received: from pps.filterd (ppma03dal.us.ibm.com [127.0.0.1]) by ppma03dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id x952GFAo026481; Sat, 5 Oct 2019 02:18:55 GMT Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by ppma03dal.us.ibm.com with ESMTP id 2v9y597hg5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 05 Oct 2019 02:18:55 +0000 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x952Is8251577146 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sat, 5 Oct 2019 02:18:54 GMT Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 045D778066; Sat, 5 Oct 2019 02:18:54 +0000 (GMT) Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CAE497805E; Sat, 5 Oct 2019 02:18:52 +0000 (GMT) Received: from [9.80.206.47] (unknown [9.80.206.47]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP; Sat, 5 Oct 2019 02:18:52 +0000 (GMT) Subject: Re: [RFC PATCH] e1000e: Use rtnl_lock to prevent race conditions between net and pci/pm From: "David Z. Dai" To: Alexander Duyck Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, intel-wired-lan@lists.osuosl.org, jeffrey.t.kirsher@intel.com, zdai@us.ibm.com, davem@davemloft.net In-Reply-To: <20191004233052.28865.1609.stgit@localhost.localdomain> References: <1570208647.1250.55.camel@oc5348122405> <20191004233052.28865.1609.stgit@localhost.localdomain> Content-Type: text/plain; charset="UTF-8" Date: Fri, 04 Oct 2019 21:18:46 -0500 Message-ID: <1570241926.10511.7.camel@oc5348122405> Mime-Version: 1.0 X-Mailer: Evolution 2.32.3 (2.32.3-36.el6) Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-10-05_01:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910050018 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, 2019-10-04 at 16:36 -0700, Alexander Duyck wrote: > From: Alexander Duyck > > This patch is meant to address possible race conditions that can exist > between network configuration and power management. A similar issue was > fixed for igb in commit 9474933caf21 ("igb: close/suspend race in > netif_device_detach"). > > In addition it consolidates the code so that the PCI error handling code > will essentially perform the power management freeze on the device prior to > attempting a reset, and will thaw the device afterwards if that is what it > is planning to do. Otherwise when we call close on the interface it should > see it is detached and not attempt to call the logic to down the interface > and free the IRQs again. > > >From what I can tell the check that was adding the check for __E1000_DOWN > in e1000e_close was added when runtime power management was added. However > it should not be relevant for us as we perform a call to > pm_runtime_get_sync before we call e1000_down/free_irq so it should always > be back up before we call into this anyway. > > Signed-off-by: Alexander Duyck > --- > > I'm putting this out as an RFC for now. I haven't had a chance to do much > testing yet, but I have verified no build issues, and the driver appears > to load, link, and pass traffic without problems. > > This should address issues seen with either double freeing or never freeing > IRQs that have been seen on this and similar drivers in the past. > > I'll submit this formally after testing it over the weekend assuming there > are no issues. > > drivers/net/ethernet/intel/e1000e/netdev.c | 33 ++++++++++++++-------------- > 1 file changed, 17 insertions(+), 16 deletions(-) > > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c > index d7d56e42a6aa..182a2c8f12d8 100644 > --- a/drivers/net/ethernet/intel/e1000e/netdev.c > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c > @@ -4715,12 +4715,12 @@ int e1000e_close(struct net_device *netdev) > > pm_runtime_get_sync(&pdev->dev); > > - if (!test_bit(__E1000_DOWN, &adapter->state)) { > + if (netif_device_present(netdev)) { > e1000e_down(adapter, true); > e1000_free_irq(adapter); > > /* Link status message must follow this format */ > - pr_info("%s NIC Link is Down\n", adapter->netdev->name); > + pr_info("%s NIC Link is Down\n", netdev->name); > } > > napi_disable(&adapter->napi); > @@ -6299,6 +6299,7 @@ static int e1000e_pm_freeze(struct device *dev) > struct net_device *netdev = dev_get_drvdata(dev); > struct e1000_adapter *adapter = netdev_priv(netdev); > > + rtnl_lock(); > netif_device_detach(netdev); > > if (netif_running(netdev)) { > @@ -6313,6 +6314,8 @@ static int e1000e_pm_freeze(struct device *dev) > e1000e_down(adapter, false); > e1000_free_irq(adapter); > } > + rtnl_unlock(); > + > e1000e_reset_interrupt_capability(adapter); > > /* Allow time for pending master requests to run */ > @@ -6626,27 +6629,30 @@ static int __e1000_resume(struct pci_dev *pdev) > return 0; > } > > -#ifdef CONFIG_PM_SLEEP > static int e1000e_pm_thaw(struct device *dev) > { > struct net_device *netdev = dev_get_drvdata(dev); > struct e1000_adapter *adapter = netdev_priv(netdev); > + int rc = 0; > > e1000e_set_interrupt_capability(adapter); > - if (netif_running(netdev)) { > - u32 err = e1000_request_irq(adapter); > > - if (err) > - return err; > + rtnl_lock(); > + if (netif_running(netdev)) { > + rc = e1000_request_irq(adapter); > + if (rc) > + goto err_irq; > > e1000e_up(adapter); > } > > netif_device_attach(netdev); > - > - return 0; > + rtnl_unlock(); > +err_irq: > + return rc; > } > > +#ifdef CONFIG_PM_SLEEP > static int e1000e_pm_suspend(struct device *dev) > { > struct pci_dev *pdev = to_pci_dev(dev); > @@ -6821,13 +6827,11 @@ static pci_ers_result_t e1000_io_error_detected(struct pci_dev *pdev, > struct net_device *netdev = pci_get_drvdata(pdev); > struct e1000_adapter *adapter = netdev_priv(netdev); > > - netif_device_detach(netdev); > + e1000e_pm_freeze(&pdev->dev); > > if (state == pci_channel_io_perm_failure) > return PCI_ERS_RESULT_DISCONNECT; > > - if (netif_running(netdev)) > - e1000e_down(adapter, true); > pci_disable_device(pdev); > > /* Request a slot slot reset. */ > @@ -6893,10 +6897,7 @@ static void e1000_io_resume(struct pci_dev *pdev) > > e1000_init_manageability_pt(adapter); > > - if (netif_running(netdev)) > - e1000e_up(adapter); > - > - netif_device_attach(netdev); > + e1000e_pm_thaw(&pdev->dev); > > /* If the controller has AMT, do not set DRV_LOAD until the interface > * is up. For all other cases, let the f/w know that the h/w is now In e1000e_pm_thaw(), these 2 lines need to switch order to avoid deadlock. from: + rtnl_unlock(); +err_irq: to: +err_irq: + rtnl_unlock(); I will find hardware to test this patch next week. Will update the test result later. Thanks! - David