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GET /api/patches/864860/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 864860,
    "url": "http://patchwork.ozlabs.org/api/patches/864860/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20180123102841.9350-1-mika.westerberg@linux.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": "<20180123102841.9350-1-mika.westerberg@linux.intel.com>",
    "list_archive_url": null,
    "date": "2018-01-23T10:28:41",
    "name": "igb: Do not call netif_device_detach() when PCIe link goes missing",
    "commit_ref": null,
    "pull_url": null,
    "state": "accepted",
    "archived": false,
    "hash": "04b0f3e48e247b94b3a4ebd06f5568502d53d0a6",
    "submitter": {
        "id": 14534,
        "url": "http://patchwork.ozlabs.org/api/people/14534/?format=api",
        "name": "Mika Westerberg",
        "email": "mika.westerberg@linux.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/20180123102841.9350-1-mika.westerberg@linux.intel.com/mbox/",
    "series": [
        {
            "id": 24942,
            "url": "http://patchwork.ozlabs.org/api/series/24942/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/list/?series=24942",
            "date": "2018-01-23T10:28:41",
            "name": "igb: Do not call netif_device_detach() when PCIe link goes missing",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/24942/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/864860/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/864860/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"
        ],
        "Authentication-Results": "ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=osuosl.org\n\t(client-ip=140.211.166.136; helo=silver.osuosl.org;\n\tenvelope-from=intel-wired-lan-bounces@osuosl.org;\n\treceiver=<UNKNOWN>)",
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            "from fmsmga005.fm.intel.com ([10.253.24.32])\n\tby orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384;\n\t23 Jan 2018 02:28:44 -0800",
            "from black.fi.intel.com ([10.237.72.28])\n\tby fmsmga005.fm.intel.com with ESMTP; 23 Jan 2018 02:28:43 -0800",
            "by black.fi.intel.com (Postfix, from userid 1001)\n\tid 3D39E15D; Tue, 23 Jan 2018 12:28:41 +0200 (EET)"
        ],
        "X-Virus-Scanned": [
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        ],
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        "X-Amp-Result": "SKIPPED(no attachment in message)",
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        "X-ExtLoop1": "1",
        "X-IronPort-AV": "E=Sophos;i=\"5.46,400,1511856000\"; d=\"scan'208\";a=\"197896010\"",
        "From": "Mika Westerberg <mika.westerberg@linux.intel.com>",
        "To": "Jeff Kirsher <jeffrey.t.kirsher@intel.com>",
        "Date": "Tue, 23 Jan 2018 13:28:41 +0300",
        "Message-Id": "<20180123102841.9350-1-mika.westerberg@linux.intel.com>",
        "X-Mailer": "git-send-email 2.15.1",
        "X-Mailman-Approved-At": "Tue, 23 Jan 2018 15:25:41 +0000",
        "Subject": "[Intel-wired-lan] [PATCH] igb: Do not call netif_device_detach()\n\twhen PCIe link goes missing",
        "X-BeenThere": "intel-wired-lan@osuosl.org",
        "X-Mailman-Version": "2.1.24",
        "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>",
        "Cc": "Nikolay Bogoychev <nheart@gmail.com>, intel-wired-lan@lists.osuosl.org, \n\tMika Westerberg <mika.westerberg@linux.intel.com>,\n\tFerenc Boldog <ferenc.boldog@gmail.com>, netdev@vger.kernel.org",
        "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": "When the driver notices that PCIe link is gone by reading 0xffffffff\nfrom a register it clears hw->hw_addr and then calls netif_device_detach().\nThis happens when the PCIe device is physically unplugged for example\nthe user disconnected the Thunderbolt cable.\n\nHowever, netif_device_detach() prevents netif_unregister() from bringing\nthe device down properly including tearing down MSI-X vectors. This\ntriggers following crash during the driver removal:\n\n  igb 0000:0b:00.0 enp11s0f0: PCIe link lost, device now detached\n  ------------[ cut here ]------------\n  kernel BUG at drivers/pci/msi.c:352!\n  invalid opcode: 0000 [#1] PREEMPT SMP PTI\n  ...\n  Call Trace:\n   pci_disable_msix+0xc9/0xf0\n   igb_reset_interrupt_capability+0x58/0x60 [igb]\n   igb_remove+0x90/0x100 [igb]\n   pci_device_remove+0x31/0xa0\n   device_release_driver_internal+0x152/0x210\n   pci_stop_bus_device+0x78/0xa0\n   pci_stop_bus_device+0x38/0xa0\n   pci_stop_bus_device+0x38/0xa0\n   pci_stop_bus_device+0x26/0xa0\n   pci_stop_bus_device+0x38/0xa0\n   pci_stop_and_remove_bus_device+0x9/0x20\n   trim_stale_devices+0xee/0x130\n   ? _raw_spin_unlock_irqrestore+0xf/0x30\n   trim_stale_devices+0x8f/0x130\n   ? _raw_spin_unlock_irqrestore+0xf/0x30\n   trim_stale_devices+0xa1/0x130\n   ? get_slot_status+0x8b/0xc0\n   acpiphp_check_bridge.part.7+0xf9/0x140\n   acpiphp_hotplug_notify+0x170/0x1f0\n   ...\n\nTo prevent the crash do not call netif_device_detach() in igb_rd32().\nThis should be fine because hw->hw_addr is set to NULL preventing future\nhardware access of the now missing device.\n\nLink: https://bugzilla.kernel.org/show_bug.cgi?id=198181\nReported-by: Ferenc Boldog <ferenc.boldog@gmail.com>\nReported-by: Nikolay Bogoychev <nheart@gmail.com>\nSigned-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>\n---\n drivers/net/ethernet/intel/igb/igb_main.c | 3 +--\n 1 file changed, 1 insertion(+), 2 deletions(-)",
    "diff": "diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c\nindex c208753ff5b7..b1de866e70b2 100644\n--- a/drivers/net/ethernet/intel/igb/igb_main.c\n+++ b/drivers/net/ethernet/intel/igb/igb_main.c\n@@ -774,8 +774,7 @@ u32 igb_rd32(struct e1000_hw *hw, u32 reg)\n \tif (!(~value) && (!reg || !(~readl(hw_addr)))) {\n \t\tstruct net_device *netdev = igb->netdev;\n \t\thw->hw_addr = NULL;\n-\t\tnetif_device_detach(netdev);\n-\t\tnetdev_err(netdev, \"PCIe link lost, device now detached\\n\");\n+\t\tnetdev_err(netdev, \"PCIe link lost\\n\");\n \t}\n \n \treturn value;\n",
    "prefixes": []
}