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GET /api/patches/770012/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 770012,
    "url": "http://patchwork.ozlabs.org/api/patches/770012/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20170601224051.6106-11-jacob.e.keller@intel.com/",
    "project": {
        "id": 46,
        "url": "http://patchwork.ozlabs.org/api/projects/46/?format=api",
        "name": "Intel Wired Ethernet development",
        "link_name": "intel-wired-lan",
        "list_id": "intel-wired-lan.osuosl.org",
        "list_email": "intel-wired-lan@osuosl.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": "",
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<20170601224051.6106-11-jacob.e.keller@intel.com>",
    "list_archive_url": null,
    "date": "2017-06-01T22:40:46",
    "name": "[10/15] fm10k: prepare_for_reset() when we lose PCIe Link",
    "commit_ref": null,
    "pull_url": null,
    "state": "superseded",
    "archived": false,
    "hash": "e14874ea180190104c165062a9db4088aa0ca652",
    "submitter": {
        "id": 9784,
        "url": "http://patchwork.ozlabs.org/api/people/9784/?format=api",
        "name": "Jacob Keller",
        "email": "jacob.e.keller@intel.com"
    },
    "delegate": {
        "id": 68,
        "url": "http://patchwork.ozlabs.org/api/users/68/?format=api",
        "username": "jtkirshe",
        "first_name": "Jeff",
        "last_name": "Kirsher",
        "email": "jeffrey.t.kirsher@intel.com"
    },
    "mbox": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20170601224051.6106-11-jacob.e.keller@intel.com/mbox/",
    "series": [],
    "comments": "http://patchwork.ozlabs.org/api/patches/770012/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/770012/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<intel-wired-lan-bounces@osuosl.org>",
        "X-Original-To": [
            "incoming@patchwork.ozlabs.org",
            "intel-wired-lan@lists.osuosl.org"
        ],
        "Delivered-To": [
            "patchwork-incoming@bilbo.ozlabs.org",
            "intel-wired-lan@lists.osuosl.org"
        ],
        "Received": [
            "from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3wf2Pl0jGlz9sNJ\n\tfor <incoming@patchwork.ozlabs.org>;\n\tFri,  2 Jun 2017 08:41:15 +1000 (AEST)",
            "from localhost (localhost [127.0.0.1])\n\tby silver.osuosl.org (Postfix) with ESMTP id 85B0530C68;\n\tThu,  1 Jun 2017 22:41:13 +0000 (UTC)",
            "from silver.osuosl.org ([127.0.0.1])\n\tby localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024)\n\twith ESMTP id Zn3sZRoy6nw6; Thu,  1 Jun 2017 22:41:03 +0000 (UTC)",
            "from ash.osuosl.org (ash.osuosl.org [140.211.166.34])\n\tby silver.osuosl.org (Postfix) with ESMTP id E736E30C7D;\n\tThu,  1 Jun 2017 22:41:00 +0000 (UTC)",
            "from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137])\n\tby ash.osuosl.org (Postfix) with ESMTP id 73E411C3EBE\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tThu,  1 Jun 2017 22:40:57 +0000 (UTC)",
            "from localhost (localhost [127.0.0.1])\n\tby fraxinus.osuosl.org (Postfix) with ESMTP id 6D79C88B42\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tThu,  1 Jun 2017 22:40:57 +0000 (UTC)",
            "from fraxinus.osuosl.org ([127.0.0.1])\n\tby localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024)\n\twith ESMTP id QwNNoPUQTSFu for <intel-wired-lan@lists.osuosl.org>;\n\tThu,  1 Jun 2017 22:40:56 +0000 (UTC)",
            "from mga14.intel.com (mga14.intel.com [192.55.52.115])\n\tby fraxinus.osuosl.org (Postfix) with ESMTPS id C70A688B3C\n\tfor <intel-wired-lan@lists.osuosl.org>;\n\tThu,  1 Jun 2017 22:40:56 +0000 (UTC)",
            "from fmsmga001.fm.intel.com ([10.253.24.23])\n\tby fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;\n\t01 Jun 2017 15:40:56 -0700",
            "from jekeller-desk.amr.corp.intel.com ([10.166.35.158])\n\tby fmsmga001.fm.intel.com with ESMTP; 01 Jun 2017 15:40:56 -0700"
        ],
        "X-Virus-Scanned": [
            "amavisd-new at osuosl.org",
            "amavisd-new at osuosl.org"
        ],
        "X-Greylist": "domain auto-whitelisted by SQLgrey-1.7.6",
        "X-ExtLoop1": "1",
        "X-IronPort-AV": "E=Sophos; i=\"5.39,281,1493708400\"; d=\"scan'208\";\n\ta=\"1155582873\"",
        "From": "Jacob Keller <jacob.e.keller@intel.com>",
        "To": "Intel Wired LAN <intel-wired-lan@lists.osuosl.org>",
        "Date": "Thu,  1 Jun 2017 15:40:46 -0700",
        "Message-Id": "<20170601224051.6106-11-jacob.e.keller@intel.com>",
        "X-Mailer": "git-send-email 2.13.0.311.g0339965c70d6",
        "In-Reply-To": "<20170601224051.6106-1-jacob.e.keller@intel.com>",
        "References": "<20170601224051.6106-1-jacob.e.keller@intel.com>",
        "Subject": "[Intel-wired-lan] [PATCH 10/15] fm10k: prepare_for_reset() when we\n\tlose PCIe Link",
        "X-BeenThere": "intel-wired-lan@osuosl.org",
        "X-Mailman-Version": "2.1.18-1",
        "Precedence": "list",
        "List-Id": "Intel Wired Ethernet Linux Kernel Driver Development\n\t<intel-wired-lan.osuosl.org>",
        "List-Unsubscribe": "<https://lists.osuosl.org/mailman/options/intel-wired-lan>, \n\t<mailto:intel-wired-lan-request@osuosl.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.osuosl.org/pipermail/intel-wired-lan/>",
        "List-Post": "<mailto:intel-wired-lan@osuosl.org>",
        "List-Help": "<mailto:intel-wired-lan-request@osuosl.org?subject=help>",
        "List-Subscribe": "<https://lists.osuosl.org/mailman/listinfo/intel-wired-lan>, \n\t<mailto:intel-wired-lan-request@osuosl.org?subject=subscribe>",
        "MIME-Version": "1.0",
        "Content-Type": "text/plain; charset=\"us-ascii\"",
        "Content-Transfer-Encoding": "7bit",
        "Errors-To": "intel-wired-lan-bounces@osuosl.org",
        "Sender": "\"Intel-wired-lan\" <intel-wired-lan-bounces@osuosl.org>"
    },
    "content": "If we lose PCIe link, such as when an unannounced PFLR event occurs, or\nwhen a device is surprise removed, we currently detach the device and\nclose the netdev. This unfortunately leaves a lot of things still\nactive, such as the msix_mbx_pf IRQ, and Tx/Rx resources.\n\nThis can cause problems because the register reads will return\npotentially invalid values which may result in unknown driver behavior.\n\nBegin the process of resetting using fm10k_prepare_for_reset(), much in\nthe same way as the suspend and resume cycle does. This will attempt to\nshutdown as much as possible, in order to prevent possible issues.\n\nSince the __FM10K_RESETTING state is long lived, we'll also stop waiting\nfor it when we check to the fm10k_reset_subtask. This is important since\notherwise it would deadlock with the fm10k_detach_subtask. Additionally,\nstop attempting to manage the mailbox subtask if we're\ndetached/resetting, as there is nothing to do when we don't have a PCIe\naddress.\n\nOverall this produces a much cleaner shutdown and recovery cycle for\na PCIe surprise remove event.\n\nSigned-off-by: Jacob Keller <jacob.e.keller@intel.com>\n---\n drivers/net/ethernet/intel/fm10k/fm10k_pci.c | 39 +++++++++++++++++++---------\n 1 file changed, 27 insertions(+), 12 deletions(-)",
    "diff": "diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c\nindex 6a7b4c5429ae..2d94a16f9613 100644\n--- a/drivers/net/ethernet/intel/fm10k/fm10k_pci.c\n+++ b/drivers/net/ethernet/intel/fm10k/fm10k_pci.c\n@@ -141,8 +141,9 @@ static void fm10k_prepare_for_reset(struct fm10k_intfc *interface)\n \t/* put off any impending NetWatchDogTimeout */\n \tnetif_trans_update(netdev);\n \n-\twhile (test_and_set_bit(__FM10K_RESETTING, interface->state))\n-\t\tusleep_range(1000, 2000);\n+\t/* Nothing to do if a reset is already in progress */\n+\tif (test_and_set_bit(__FM10K_RESETTING, interface->state))\n+\t\treturn;\n \n \trtnl_lock();\n \n@@ -168,6 +169,8 @@ static int fm10k_handle_reset(struct fm10k_intfc *interface)\n \tstruct fm10k_hw *hw = &interface->hw;\n \tint err;\n \n+\tWARN_ON(!test_bit(__FM10K_RESETTING, interface->state));\n+\n \trtnl_lock();\n \n \tpci_set_master(interface->pdev);\n@@ -247,27 +250,33 @@ static void fm10k_detach_subtask(struct fm10k_intfc *interface)\n \tu32 __iomem *hw_addr;\n \tu32 value;\n \n-\t/* do nothing if device is still present or hw_addr is set */\n+\t/* do nothing if netdev is still present or hw_addr is set */\n \tif (netif_device_present(netdev) || interface->hw.hw_addr)\n \t\treturn;\n \n+\t/* We've lost the PCIe register space, and can no longer access the\n+\t * device. Shut everything except the detach subtask down and prepare\n+\t * to reset the device in case we recover.\n+\t */\n+\tfm10k_prepare_for_reset(interface);\n+\n \t/* check the real address space to see if we've recovered */\n \thw_addr = READ_ONCE(interface->uc_addr);\n \tvalue = readl(hw_addr);\n \tif (~value) {\n+\t\t/* Restore the hardware address */\n \t\tinterface->hw.hw_addr = interface->uc_addr;\n+\n+\t\t/* PCIe link has been restored, and the device is active\n+\t\t * again. Restore everything and reset the device.\n+\t\t */\n+\t\tfm10k_handle_reset(interface);\n+\n+\t\t/* Re-attach the netdev */\n \t\tnetif_device_attach(netdev);\n-\t\tset_bit(FM10K_FLAG_RESET_REQUESTED, interface->flags);\n \t\tnetdev_warn(netdev, \"PCIe link restored, device now attached\\n\");\n \t\treturn;\n \t}\n-\n-\trtnl_lock();\n-\n-\tif (netif_running(netdev))\n-\t\tdev_close(netdev);\n-\n-\trtnl_unlock();\n }\n \n static void fm10k_reinit(struct fm10k_intfc *interface)\n@@ -360,6 +369,10 @@ static void fm10k_watchdog_update_host_state(struct fm10k_intfc *interface)\n  **/\n static void fm10k_mbx_subtask(struct fm10k_intfc *interface)\n {\n+\t/* If we're resetting, bail out */\n+\tif (test_bit(__FM10K_RESETTING, interface->state))\n+\t\treturn;\n+\n \t/* process upstream mailbox and update device state */\n \tfm10k_watchdog_update_host_state(interface);\n \n@@ -609,9 +622,11 @@ static void fm10k_service_task(struct work_struct *work)\n \n \tinterface = container_of(work, struct fm10k_intfc, service_task);\n \n+\t/* Check whether we're detached first */\n+\tfm10k_detach_subtask(interface);\n+\n \t/* tasks run even when interface is down */\n \tfm10k_mbx_subtask(interface);\n-\tfm10k_detach_subtask(interface);\n \tfm10k_reset_subtask(interface);\n \n \t/* tasks only run when interface is up */\n",
    "prefixes": [
        "10/15"
    ]
}