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GET /api/patches/1305983/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 1305983,
    "url": "http://patchwork.ozlabs.org/api/patches/1305983/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/patch/20200609131945.18373-2-ciara.loftus@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": "<20200609131945.18373-2-ciara.loftus@intel.com>",
    "list_archive_url": null,
    "date": "2020-06-09T13:19:44",
    "name": "[net,2/3] i40e: protect ring accesses with READ- and WRITE_ONCE",
    "commit_ref": null,
    "pull_url": null,
    "state": "accepted",
    "archived": false,
    "hash": "a2a4699173e0b7f32f8caba4b70bca1ff881b572",
    "submitter": {
        "id": 67255,
        "url": "http://patchwork.ozlabs.org/api/people/67255/?format=api",
        "name": "Ciara Loftus",
        "email": "ciara.loftus@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/20200609131945.18373-2-ciara.loftus@intel.com/mbox/",
    "series": [
        {
            "id": 182261,
            "url": "http://patchwork.ozlabs.org/api/series/182261/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/intel-wired-lan/list/?series=182261",
            "date": "2020-06-09T13:19:43",
            "name": "[net,1/3] ixgbe: protect ring accesses with READ- and WRITE_ONCE",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/182261/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/1305983/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/1305983/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": [
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        ],
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            "from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 49hB8n1P67z9sRK\n\tfor <incoming@patchwork.ozlabs.org>; Tue,  9 Jun 2020 23:40:57 +1000 (AEST)",
            "from localhost (localhost [127.0.0.1])\n\tby silver.osuosl.org (Postfix) with ESMTP id 86CF822812;\n\tTue,  9 Jun 2020 13:40:55 +0000 (UTC)",
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            "from silver.osuosl.org ([127.0.0.1])\n by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024)\n with ESMTP id gfEWhFEyPs2g for <intel-wired-lan@lists.osuosl.org>;\n Tue,  9 Jun 2020 13:40:50 +0000 (UTC)",
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            "from fmsmga004.fm.intel.com ([10.253.24.48])\n by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384;\n 09 Jun 2020 06:40:49 -0700",
            "from silpixa00399839.ir.intel.com (HELO localhost.localdomain)\n ([10.237.222.8])\n by fmsmga004.fm.intel.com with ESMTP; 09 Jun 2020 06:40:48 -0700"
        ],
        "X-Virus-Scanned": [
            "amavisd-new at osuosl.org",
            "amavisd-new at osuosl.org"
        ],
        "X-Greylist": "domain auto-whitelisted by SQLgrey-1.7.6",
        "IronPort-SDR": [
            "\n OvWCwcIBpr8qk0dsciVV83WswZ4jHzFqDNpcfPgeuU7P5pgIxpVzJz2wViCH9g1B+FjEi2hab1\n Snq3zWH2CPQA==",
            "\n ECVqyDBtTLe+m4htIZcsDLANRgIAyAN6h2NxYDwRiGAwljoEWYmcT36CjszigxgqFE9SSwqVs0\n Cv7OHMzLnxew=="
        ],
        "X-Amp-Result": "SKIPPED(no attachment in message)",
        "X-Amp-File-Uploaded": "False",
        "X-ExtLoop1": "1",
        "X-IronPort-AV": "E=Sophos;i=\"5.73,492,1583222400\"; d=\"scan'208\";a=\"295837449\"",
        "From": "Ciara Loftus <ciara.loftus@intel.com>",
        "To": "intel-wired-lan@lists.osuosl.org",
        "Date": "Tue,  9 Jun 2020 13:19:44 +0000",
        "Message-Id": "<20200609131945.18373-2-ciara.loftus@intel.com>",
        "X-Mailer": "git-send-email 2.17.1",
        "In-Reply-To": "<20200609131945.18373-1-ciara.loftus@intel.com>",
        "References": "<20200609131945.18373-1-ciara.loftus@intel.com>",
        "MIME-Version": "1.0",
        "Subject": "[Intel-wired-lan] [PATCH net 2/3] i40e: protect ring accesses with\n READ- and WRITE_ONCE",
        "X-BeenThere": "intel-wired-lan@osuosl.org",
        "X-Mailman-Version": "2.1.29",
        "Precedence": "list",
        "List-Id": "Intel Wired Ethernet Linux Kernel Driver Development\n <intel-wired-lan.osuosl.org>",
        "List-Unsubscribe": "<https://lists.osuosl.org/mailman/options/intel-wired-lan>,\n <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 <mailto:intel-wired-lan-request@osuosl.org?subject=subscribe>",
        "Cc": "netdev@vger.kernel.org, bjorn.topel@intel.com, magnus.karlsson@intel.com",
        "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": "READ_ONCE should be used when reading rings prior to accessing the\nstatistics pointer. Introduce this as well as the corresponding WRITE_ONCE\nusage when allocating and freeing the rings, to ensure protected access.\n\nSigned-off-by: Ciara Loftus <ciara.loftus@intel.com>\n---\n drivers/net/ethernet/intel/i40e/i40e_main.c | 29 ++++++++++++++-------\n 1 file changed, 19 insertions(+), 10 deletions(-)",
    "diff": "diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c\nindex 5d807c8004f8..56ecd6c3f236 100644\n--- a/drivers/net/ethernet/intel/i40e/i40e_main.c\n+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c\n@@ -439,11 +439,15 @@ static void i40e_get_netdev_stats_struct(struct net_device *netdev,\n \t\ti40e_get_netdev_stats_struct_tx(ring, stats);\n \n \t\tif (i40e_enabled_xdp_vsi(vsi)) {\n-\t\t\tring++;\n+\t\t\tring = READ_ONCE(vsi->xdp_rings[i]);\n+\t\t\tif (!ring)\n+\t\t\t\tcontinue;\n \t\t\ti40e_get_netdev_stats_struct_tx(ring, stats);\n \t\t}\n \n-\t\tring++;\n+\t\tring = READ_ONCE(vsi->rx_rings[i]);\n+\t\tif (!ring)\n+\t\t\tcontinue;\n \t\tdo {\n \t\t\tstart   = u64_stats_fetch_begin_irq(&ring->syncp);\n \t\t\tpackets = ring->stats.packets;\n@@ -787,6 +791,8 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)\n \tfor (q = 0; q < vsi->num_queue_pairs; q++) {\n \t\t/* locate Tx ring */\n \t\tp = READ_ONCE(vsi->tx_rings[q]);\n+\t\tif (!p)\n+\t\t\tcontinue;\n \n \t\tdo {\n \t\t\tstart = u64_stats_fetch_begin_irq(&p->syncp);\n@@ -800,8 +806,11 @@ static void i40e_update_vsi_stats(struct i40e_vsi *vsi)\n \t\ttx_linearize += p->tx_stats.tx_linearize;\n \t\ttx_force_wb += p->tx_stats.tx_force_wb;\n \n-\t\t/* Rx queue is part of the same block as Tx queue */\n-\t\tp = &p[1];\n+\t\t/* locate Rx ring */\n+\t\tp = READ_ONCE(vsi->rx_rings[q]);\n+\t\tif (!p)\n+\t\t\tcontinue;\n+\n \t\tdo {\n \t\t\tstart = u64_stats_fetch_begin_irq(&p->syncp);\n \t\t\tpackets = p->stats.packets;\n@@ -10824,10 +10833,10 @@ static void i40e_vsi_clear_rings(struct i40e_vsi *vsi)\n \tif (vsi->tx_rings && vsi->tx_rings[0]) {\n \t\tfor (i = 0; i < vsi->alloc_queue_pairs; i++) {\n \t\t\tkfree_rcu(vsi->tx_rings[i], rcu);\n-\t\t\tvsi->tx_rings[i] = NULL;\n-\t\t\tvsi->rx_rings[i] = NULL;\n+\t\t\tWRITE_ONCE(vsi->tx_rings[i], NULL);\n+\t\t\tWRITE_ONCE(vsi->rx_rings[i], NULL);\n \t\t\tif (vsi->xdp_rings)\n-\t\t\t\tvsi->xdp_rings[i] = NULL;\n+\t\t\t\tWRITE_ONCE(vsi->xdp_rings[i], NULL);\n \t\t}\n \t}\n }\n@@ -10861,7 +10870,7 @@ static int i40e_alloc_rings(struct i40e_vsi *vsi)\n \t\tif (vsi->back->hw_features & I40E_HW_WB_ON_ITR_CAPABLE)\n \t\t\tring->flags = I40E_TXR_FLAGS_WB_ON_ITR;\n \t\tring->itr_setting = pf->tx_itr_default;\n-\t\tvsi->tx_rings[i] = ring++;\n+\t\tWRITE_ONCE(vsi->tx_rings[i], ring++);\n \n \t\tif (!i40e_enabled_xdp_vsi(vsi))\n \t\t\tgoto setup_rx;\n@@ -10879,7 +10888,7 @@ static int i40e_alloc_rings(struct i40e_vsi *vsi)\n \t\t\tring->flags = I40E_TXR_FLAGS_WB_ON_ITR;\n \t\tset_ring_xdp(ring);\n \t\tring->itr_setting = pf->tx_itr_default;\n-\t\tvsi->xdp_rings[i] = ring++;\n+\t\tWRITE_ONCE(vsi->xdp_rings[i], ring++);\n \n setup_rx:\n \t\tring->queue_index = i;\n@@ -10892,7 +10901,7 @@ static int i40e_alloc_rings(struct i40e_vsi *vsi)\n \t\tring->size = 0;\n \t\tring->dcb_tc = 0;\n \t\tring->itr_setting = pf->rx_itr_default;\n-\t\tvsi->rx_rings[i] = ring;\n+\t\tWRITE_ONCE(vsi->rx_rings[i], ring);\n \t}\n \n \treturn 0;\n",
    "prefixes": [
        "net",
        "2/3"
    ]
}