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GET /api/patches/815477/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
Content-Type: application/json
Vary: Accept

{
    "id": 815477,
    "url": "http://patchwork.ozlabs.org/api/patches/815477/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/patch/20170919115055.19278-3-jgross@suse.com/",
    "project": {
        "id": 14,
        "url": "http://patchwork.ozlabs.org/api/projects/14/?format=api",
        "name": "QEMU Development",
        "link_name": "qemu-devel",
        "list_id": "qemu-devel.nongnu.org",
        "list_email": "qemu-devel@nongnu.org",
        "web_url": "",
        "scm_url": "",
        "webscm_url": "",
        "list_archive_url": "",
        "list_archive_url_format": "",
        "commit_url_format": ""
    },
    "msgid": "<20170919115055.19278-3-jgross@suse.com>",
    "list_archive_url": null,
    "date": "2017-09-19T11:50:55",
    "name": "[2/2] xen: dont try setting max grants multiple times",
    "commit_ref": null,
    "pull_url": null,
    "state": "new",
    "archived": false,
    "hash": "ec0d6d0ff65be1652b02aadd01de5898ad0e5566",
    "submitter": {
        "id": 64874,
        "url": "http://patchwork.ozlabs.org/api/people/64874/?format=api",
        "name": "Jürgen Groß",
        "email": "jgross@suse.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/qemu-devel/patch/20170919115055.19278-3-jgross@suse.com/mbox/",
    "series": [
        {
            "id": 3854,
            "url": "http://patchwork.ozlabs.org/api/series/3854/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/list/?series=3854",
            "date": "2017-09-19T11:50:55",
            "name": "xen: fix gnttab handling with old dom0 kernels",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/3854/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/815477/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/815477/checks/",
    "tags": {},
    "related": [],
    "headers": {
        "Return-Path": "<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>",
        "X-Original-To": "incoming@patchwork.ozlabs.org",
        "Delivered-To": "patchwork-incoming@bilbo.ozlabs.org",
        "Authentication-Results": "ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=<UNKNOWN>)",
        "Received": [
            "from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xxLnc0XhZz9s7m\n\tfor <incoming@patchwork.ozlabs.org>;\n\tTue, 19 Sep 2017 21:51:48 +1000 (AEST)",
            "from localhost ([::1]:41947 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>)\n\tid 1duH46-0002DW-4Q\n\tfor incoming@patchwork.ozlabs.org; Tue, 19 Sep 2017 07:51:46 -0400",
            "from eggs.gnu.org ([2001:4830:134:3::10]:36329)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from <jgross@suse.com>) id 1duH3U-0002CJ-EK\n\tfor qemu-devel@nongnu.org; Tue, 19 Sep 2017 07:51:09 -0400",
            "from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from <jgross@suse.com>) id 1duH3R-0006Bz-QM\n\tfor qemu-devel@nongnu.org; Tue, 19 Sep 2017 07:51:08 -0400",
            "from mx2.suse.de ([195.135.220.15]:47678 helo=mx1.suse.de)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from <jgross@suse.com>) id 1duH3R-0006AR-Jc\n\tfor qemu-devel@nongnu.org; Tue, 19 Sep 2017 07:51:05 -0400",
            "from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254])\n\tby mx1.suse.de (Postfix) with ESMTP id 593295CBC1;\n\tTue, 19 Sep 2017 11:51:03 +0000 (UTC)"
        ],
        "X-Virus-Scanned": "by amavisd-new at test-mx.suse.de",
        "From": "Juergen Gross <jgross@suse.com>",
        "To": "qemu-devel@nongnu.org,\n\txen-devel@lists.xenproject.org",
        "Date": "Tue, 19 Sep 2017 13:50:55 +0200",
        "Message-Id": "<20170919115055.19278-3-jgross@suse.com>",
        "X-Mailer": "git-send-email 2.12.3",
        "In-Reply-To": "<20170919115055.19278-1-jgross@suse.com>",
        "References": "<20170919115055.19278-1-jgross@suse.com>",
        "X-detected-operating-system": "by eggs.gnu.org: GNU/Linux 2.2.x-3.x (no\n\ttimestamps) [generic] [fuzzy]",
        "X-Received-From": "195.135.220.15",
        "Subject": "[Qemu-devel] [PATCH 2/2] xen: dont try setting max grants multiple\n\ttimes",
        "X-BeenThere": "qemu-devel@nongnu.org",
        "X-Mailman-Version": "2.1.21",
        "Precedence": "list",
        "List-Id": "<qemu-devel.nongnu.org>",
        "List-Unsubscribe": "<https://lists.nongnu.org/mailman/options/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>",
        "List-Archive": "<http://lists.nongnu.org/archive/html/qemu-devel/>",
        "List-Post": "<mailto:qemu-devel@nongnu.org>",
        "List-Help": "<mailto:qemu-devel-request@nongnu.org?subject=help>",
        "List-Subscribe": "<https://lists.nongnu.org/mailman/listinfo/qemu-devel>,\n\t<mailto:qemu-devel-request@nongnu.org?subject=subscribe>",
        "Cc": "anthony.perard@citrix.com, Juergen Gross <jgross@suse.com>,\n\tsstabellini@kernel.org, kraxel@redhat.com",
        "Errors-To": "qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org",
        "Sender": "\"Qemu-devel\"\n\t<qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org>"
    },
    "content": "Trying to call xengnttab_set_max_grants() with the same file handle\nmight fail on some kernels, as this operation is allowed only once.\n\nThis is a problem for the qdisk backend as blk_connect() can be\ncalled multiple times for a domain, e.g. in case grub-xen is being\nused to boot it.\n\nSo instead of letting the generic backend code open the gnttab device\ndo it in blk_connect() and close it again in blk_disconnect.\n\nSigned-off-by: Juergen Gross <jgross@suse.com>\n---\n hw/block/xen_disk.c | 12 +++++++++++-\n 1 file changed, 11 insertions(+), 1 deletion(-)",
    "diff": "diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c\nindex 6632746250..7cff8863cb 100644\n--- a/hw/block/xen_disk.c\n+++ b/hw/block/xen_disk.c\n@@ -1220,6 +1220,12 @@ static int blk_connect(struct XenDevice *xendev)\n     /* Add on the number needed for the ring pages */\n     max_grants += blkdev->nr_ring_ref;\n \n+    blkdev->xendev.gnttabdev = xengnttab_open(NULL, 0);\n+    if (blkdev->xendev.gnttabdev == NULL) {\n+        xen_pv_printf(xendev, 0, \"xengnttab_open failed: %s\\n\",\n+                      strerror(errno));\n+        return -1;\n+    }\n     if (xengnttab_set_max_grants(blkdev->xendev.gnttabdev, max_grants)) {\n         xen_pv_printf(xendev, 0, \"xengnttab_set_max_grants failed: %s\\n\",\n                       strerror(errno));\n@@ -1327,6 +1333,11 @@ static void blk_disconnect(struct XenDevice *xendev)\n         }\n         blkdev->feature_persistent = false;\n     }\n+\n+    if (blkdev->xendev.gnttabdev) {\n+        xengnttab_close(blkdev->xendev.gnttabdev);\n+        blkdev->xendev.gnttabdev = NULL;\n+    }\n }\n \n static int blk_free(struct XenDevice *xendev)\n@@ -1363,7 +1374,6 @@ static void blk_event(struct XenDevice *xendev)\n \n struct XenDevOps xen_blkdev_ops = {\n     .size       = sizeof(struct XenBlkDev),\n-    .flags      = DEVOPS_FLAG_NEED_GNTDEV,\n     .alloc      = blk_alloc,\n     .init       = blk_init,\n     .initialise    = blk_connect,\n",
    "prefixes": [
        "2/2"
    ]
}