From nobody Mon Apr 6 13:28:24 2026 Received: from BN8PR05CU002.outbound.protection.outlook.com (mail-eastus2azon11011056.outbound.protection.outlook.com [52.101.57.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4046C382F1F; Sun, 5 Apr 2026 20:52:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.57.56 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775422353; cv=fail; b=fd6AmgL13TSTaO09FC1mMQtOrVlTfumSWIB93CBwM7PHAUoWwoPhuuq2sslGeBpcNbEOHC5WjudQxhrJFjOQ4/jdBEpjBbSDz9eqXmuCpJlahBWCSuLY4oq5w3DKEqLYNYlnE4cuvmHbtnPhxa8dotkXcSBvh70KsmgmahQR25o= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775422353; c=relaxed/simple; bh=Fee1vMZvAuGQ+EfNLsUV4Ei4fYleIw/O+Z8Lu6riMLk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: Content-Type:MIME-Version; b=O9siIxnJ7oiLB/TyJffrAKUvm6Dq7/x39uLWa4XTJr8MVIV65TDJxCHkCJq3Bpr0bRNs4VMqM+34SitvmNN+2gFmjB0GgiLOWK8LjGZ+e828RAo2qzxman8cYim8HPAYLwvja5b2n8LzhK6AsVLpnNYv1V8oKaRnK7GAxM8+lyE= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com; spf=fail smtp.mailfrom=nvidia.com; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b=mn3Pf5f7; arc=fail smtp.client-ip=52.101.57.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=nvidia.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=nvidia.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=Nvidia.com header.i=@Nvidia.com header.b="mn3Pf5f7" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=nyHSrO5M3ogJ/N8tk+HVpwXw2h7vEdye7A1wSn73SVmUDO9/VvLWMkF1Y5W/9v+stbFrmfhIU+2h2/9xlVW3bDXuEwY5rl/OodpYtBVHLT3gMwqzcKsurB9BAEIIUgsktpoiBCU9MJaxPdKkuMBe2wJWRyb1UcRXMPh7UOSSt1OBxEvaLbkD0GXxoyRrTBkFd8YXU65gFpT2QAlkAhEhOzRDQXoPT/sP9T41LF0k0s3U7fgK5bqO+f0r9tqd+AQlhm9VRfpfMawNZWjEDSBt/F9S7flwIS1G6vPS/9rr3uAhwpdr3XQk8c7tJtCN1mibiMvJmMpnv3MCAZR2k/H/+A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=k0BRg1fv40I035l3aZzAKgIRnWsr3oWjMBhhxfomsr8=; b=PBBdWC+rtdJOKGv9TRr1iacZGlmKAGMCQy+mIc27VM47epZ9ZJDIjrTHs4MznLqhS9ZER5FJqvm0lTwuPqGtBkxL20sxdJCVpNb9/sZfm3NyAvx5HTjg+OjuPsgXcY/ssVB7HejAiUrydgYPRCkx4po5odeiQ/Vp7jjlH7E8dpqFj8R0XI0BI5RnMovCnQfy3DQ9EEK0uR4qVMsjv3mK9Ac+m3ApD4Ylu3rSXaeE+q8nFLwPxDMEedBJszdgeQyxHOoDjJI0EJM/wGUFoYfK5AMdvLIG8r6yH0SI3YprFPK19jxtQ5sSoL9Wtr32w6wBZZx2VOf1QAqMBmjlgotcqA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=k0BRg1fv40I035l3aZzAKgIRnWsr3oWjMBhhxfomsr8=; b=mn3Pf5f7fhtZAWfX/piSuCiWiiCanypzPmqNCpGEHULnlQhGAIUqKCg/ScJBE4cx0FFE1pJbHoFNIV8CPTKh6WU4gkWR1gQFOFhatbh8LrXAuoBU4rYiXO7EjNR3PqjQ4IV4ooFnqbwD10sNxQS14aDTSlK0u2B98gX8faz6QwFl0tmIKUtqj+tSEYYwI4L/KZj+16eTr/N9JDTRTktl59dJuw3hwM8y/sb77N19ZCv4Vk5IO3vQ+Xtzo86mkPLMOXAiGI3vlhoSUutALlJicbR4qDZiSaVC7cXpql8npUrdJencdntysBpXcZ6h13rHfCv561GIQlEcHBFv/Rjgug== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from DS7PR12MB8202.namprd12.prod.outlook.com (2603:10b6:8:e1::13) by SJ2PR12MB8807.namprd12.prod.outlook.com (2603:10b6:a03:4d0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9769.17; Sun, 5 Apr 2026 20:52:27 +0000 Received: from DS7PR12MB8202.namprd12.prod.outlook.com ([fe80::38fd:4146:aea:639e]) by DS7PR12MB8202.namprd12.prod.outlook.com ([fe80::38fd:4146:aea:639e%6]) with mapi id 15.20.9769.020; Sun, 5 Apr 2026 20:52:27 +0000 From: Andy Roulin To: netdev@vger.kernel.org Cc: bridge@lists.linux.dev, Nikolay Aleksandrov , Ido Schimmel , Andrew Lunn , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , Petr Machata , Donald Hunter , Jonas Gorski , linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Andy Roulin , Nikolay Aleksandrov Subject: [PATCH net-next v4 1/3] net: bridge: add stp_mode attribute for STP mode selection Date: Sun, 5 Apr 2026 13:52:22 -0700 Message-ID: <20260405205224.3163000-2-aroulin@nvidia.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260405205224.3163000-1-aroulin@nvidia.com> References: <20260405205224.3163000-1-aroulin@nvidia.com> Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: BYAPR08CA0043.namprd08.prod.outlook.com (2603:10b6:a03:117::20) To DS7PR12MB8202.namprd12.prod.outlook.com (2603:10b6:8:e1::13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS7PR12MB8202:EE_|SJ2PR12MB8807:EE_ X-MS-Office365-Filtering-Correlation-Id: 010714e4-4ad5-476c-1abc-08de93553f5a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|7416014|22082099003|56012099003|18092099006|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS7PR12MB8202.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014)(7416014)(22082099003)(56012099003)(18092099006)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?SBohUg7C5KqCv2YFMRewJVlTY2DEz160sdJRDstpYEsWRA+gqsAl9Ad0/UGG?= =?us-ascii?Q?ZjbHuKnVcra8ACc07G9xxxuhvcsroVnCaGLXQx2zbR8OPgbXJgqKTmAFesLr?= =?us-ascii?Q?K3FLgsxUew9/VjZpGg9WDrNjP664bCDuU3fNhi+vG63fxr+tHGiwpwSVh2/S?= =?us-ascii?Q?21g6L0LYaQjHQClKJoX6OSwV0uzHC6KLF+gdECLzcVTzm7tOHun66UZDxU+G?= =?us-ascii?Q?6gbmT0dzCoP0qkONxaqR+K4nEiZQbH1OadId/wk0kMccob2ss/c1tQLMl2f5?= =?us-ascii?Q?8k6EwArnJkSjlA4eamKeF2B98cBYgxnHW2D1AN6zbKTO3r9H2upXiuDmcWsg?= =?us-ascii?Q?OyHwtfjn3FODQ8PPgZf/ohU2qDkE0mXFBdC8fwluRUoC0aXXN15j4ce3sUnn?= =?us-ascii?Q?mfazVUwWew1xQR9N5bU+hhV6871OJtrndPn62X0NXgzg80OLYBQhuieJ7uXm?= =?us-ascii?Q?8zgyi+aHswFmrie29N8XDhVxCLnnChwaPpQL665K1XNf9vFuUIyutWSQ0AIr?= =?us-ascii?Q?ziihy0nIxuWaeWHT/+KI5+5/IxRgWN8V3xrmZCAShK2s/Vizw9bVXS0O+6j4?= =?us-ascii?Q?+ir7M6CVk0eSpkA+kaL7kqbd0p6qSvG+CZEmYDw+pHWGq3VNm03CmZraW4Cy?= =?us-ascii?Q?DFdiN/wezP7XqdEDp0YKC/xrMTfmHk00syrF/o4ztb+7KYwljXFF4jegcgJ0?= =?us-ascii?Q?/wqvVzOE+pU1VwMYFCd90xjvKiyLpflw2dkU6Hm8YX/nHvOjPGCdBDSZ/KPR?= =?us-ascii?Q?67AI1doS9b/rS25km3xlrFxkSi/eWuTITd5Q2YQdWPVIe66LHW+zSdzIDMxi?= =?us-ascii?Q?Y94F5pHQmCqVBJo4osZEqK/zMiyHYWZMeR6kY4rJlM26RekYiQeBapwt+7bR?= =?us-ascii?Q?cfjuK+9XrYfTrAW16im62gxAdu2RgM5JIQh6VL/GmxpXNxjZMpYwXrlyBCrU?= =?us-ascii?Q?uzlmgO1J+C+NRL/vjymeAh8Q/V9ywOJNQZZ4YklXOKtnOKQBBW165oHXGXKB?= =?us-ascii?Q?Mo1D/YOaZ81l8wlygozZfeLDolvL0C4Ul7qKJhqd62PXeshf7aoNj5gd79qC?= =?us-ascii?Q?8phRLhCK98PRniKilEjRN/lLmwavBJV6JSP6QigHoa63wxewe9ShZQ7bM9l+?= =?us-ascii?Q?aZpTEHBxMv6erblZIsWIP3b+2Cj4cKOMKjvq3Ic7E6VN52SkEY7blkJD1V/q?= =?us-ascii?Q?MB0JHq7CQgYYhkSg+6W4Sq39Va6Mdys42TzVNsWGcaxV1uW08rKNZT09cJKO?= =?us-ascii?Q?5lajy1sibExl0sOZPNrYWmL3k7062nJPrFH8UKSU42W7lEFbsj5tMdsQkXRn?= =?us-ascii?Q?yL8qL9eGdDv9z/Z0l/AWOGWEHd/uphl6zSUr537SaFm4DjQb5yURvMmEoDws?= =?us-ascii?Q?rb+Ynah6jSHwOWk1g25N7uJA+qwrWqeDvWKa4VLrBaBhgukMxH2CAkqk0W68?= =?us-ascii?Q?b14FCy9IzcfHu6IuYQwzaDtSOVduIUz0Yh3KeINRIkTOryip8QghYRjjAtJD?= =?us-ascii?Q?WGVNOrdxREsIakYeMLim3RG9S6clsbQm/obKC9Pl1RAEFJeVQbLu3kX+y3jV?= =?us-ascii?Q?ihl/ovDqNcreNLdFI1cejTBAosM7ph9DMu0JykUoXseRrPmrhEwlPA/hDhT2?= =?us-ascii?Q?ciwJ0wGJArQtLgYJ4aYI1dYil7FK9DvfuisVK8Q9Hr5SKU1yBe+CXj1JCRmz?= =?us-ascii?Q?MvdiaW/Cakw9DouHpygibZPzH6Nnmzz2Zv7g79E6N5bHMfhr2zBZ9s3mynql?= =?us-ascii?Q?/W0S4Gl5Ew=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 010714e4-4ad5-476c-1abc-08de93553f5a X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB8202.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 Apr 2026 20:52:27.8350 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: S6hgpmYPgptso/d0g8aNCR8sQF39LFRJ6EycfHly0gSOoON7Ji3cvt/AvGqinKjM3ORG1VxZF9tj6kjm1mQpmw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ2PR12MB8807 Content-Type: text/plain; charset="utf-8" The bridge-stp usermode helper is currently restricted to the initial network namespace, preventing userspace STP daemons (e.g. mstpd) from operating on bridges in other network namespaces. Since commit ff62198553e4 ("bridge: Only call /sbin/bridge-stp for the initial network namespace"), bridges in non-init namespaces silently fall back to kernel STP with no way to use userspace STP. Add a new bridge attribute IFLA_BR_STP_MODE that allows explicit per-bridge control over STP mode selection: BR_STP_MODE_AUTO (default) - Existing behavior: invoke the /sbin/bridge-stp helper in init_net only; fall back to kernel STP if it fails or in non-init namespaces. BR_STP_MODE_USER - Directly enable userspace STP (BR_USER_STP) without invoking the helper. Works in any network namespace. Userspace is responsible for ensuring an STP daemon manages the bridge. BR_STP_MODE_KERNEL - Directly enable kernel STP (BR_KERNEL_STP) without invoking the helper. The mode can only be changed while STP is disabled, or set to the same value (-EBUSY otherwise). IFLA_BR_STP_MODE is processed before IFLA_BR_STP_STATE in br_changelink(), so both can be set atomically in a single netlink message. The mode can also be changed in the same message that disables STP. The stp_mode struct field is u8 since all possible values fit, while NLA_U32 is used for the netlink attribute since it occupies the same space in the netlink message as NLA_U8. A new stp_helper_active boolean tracks whether the /sbin/bridge-stp helper was invoked during br_stp_start(), so that br_stp_stop() only calls the helper for stop when it was called for start. This avoids calling the helper asymmetrically when stp_mode changes between start and stop. Suggested-by: Ido Schimmel Assisted-by: Claude:claude-opus-4-6 Reviewed-by: Ido Schimmel Acked-by: Nikolay Aleksandrov Signed-off-by: Andy Roulin --- Notes: v2: * Add rt-link.yaml netlink spec update. * Allow idempotent stp_mode set while STP is active. * Move stp_mode next to root_port to fill a struct hole. * Rephrase BR_STP_MODE_USER doc. v3: * Name enum br_stp_mode for YNL codegen. * Add enum-name to rt-link.yaml spec. v4: * Use u8 for stp_mode struct field. * Add stp_helper_active bool to track whether the usermode helper was invoked during start. * Allow mode change when STP is being disabled in the same netlink message. Documentation/netlink/specs/rt-link.yaml | 12 ++++++++ include/uapi/linux/if_link.h | 39 ++++++++++++++++++++++++ net/bridge/br_device.c | 1 + net/bridge/br_netlink.c | 24 ++++++++++++++- net/bridge/br_private.h | 2 ++ net/bridge/br_stp_if.c | 19 +++++++----- 6 files changed, 89 insertions(+), 8 deletions(-) diff --git a/Documentation/netlink/specs/rt-link.yaml b/Documentation/netli= nk/specs/rt-link.yaml index df4b56beb8187..495836a569e8f 100644 --- a/Documentation/netlink/specs/rt-link.yaml +++ b/Documentation/netlink/specs/rt-link.yaml @@ -833,6 +833,14 @@ definitions: entries: - p2p - mp + - + name: br-stp-mode + type: enum + enum-name: br-stp-mode + entries: + - auto + - user + - kernel =20 attribute-sets: - @@ -1543,6 +1551,10 @@ attribute-sets: - name: fdb-max-learned type: u32 + - + name: stp-mode + type: u32 + enum: br-stp-mode - name: linkinfo-brport-attrs name-prefix: ifla-brport- diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 83a96c56b8cad..f159be39a6e78 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -744,6 +744,11 @@ enum in6_addr_gen_mode { * @IFLA_BR_FDB_MAX_LEARNED * Set the number of max dynamically learned FDB entries for the current * bridge. + * + * @IFLA_BR_STP_MODE + * Set the STP mode for the bridge, which controls how the bridge + * selects between userspace and kernel STP. The valid values are + * documented below in the ``BR_STP_MODE_*`` constants. */ enum { IFLA_BR_UNSPEC, @@ -796,11 +801,45 @@ enum { IFLA_BR_MCAST_QUERIER_STATE, IFLA_BR_FDB_N_LEARNED, IFLA_BR_FDB_MAX_LEARNED, + IFLA_BR_STP_MODE, __IFLA_BR_MAX, }; =20 #define IFLA_BR_MAX (__IFLA_BR_MAX - 1) =20 +/** + * DOC: Bridge STP mode values + * + * @BR_STP_MODE_AUTO + * Default. The kernel invokes the ``/sbin/bridge-stp`` helper to hand + * the bridge to a userspace STP daemon (e.g. mstpd). Only attempted in + * the initial network namespace; in other namespaces this falls back to + * kernel STP. + * + * @BR_STP_MODE_USER + * Directly enable userspace STP (``BR_USER_STP``) without invoking the + * ``/sbin/bridge-stp`` helper. Works in any network namespace. + * Userspace is responsible for ensuring an STP daemon manages the + * bridge. + * + * @BR_STP_MODE_KERNEL + * Directly enable kernel STP (``BR_KERNEL_STP``) without invoking the + * helper. + * + * The mode controls how the bridge selects between userspace and kernel + * STP when STP is enabled via ``IFLA_BR_STP_STATE``. It can only be + * changed while STP is disabled (``IFLA_BR_STP_STATE`` =3D=3D 0), returns + * ``-EBUSY`` otherwise. The default value is ``BR_STP_MODE_AUTO``. + */ +enum br_stp_mode { + BR_STP_MODE_AUTO, + BR_STP_MODE_USER, + BR_STP_MODE_KERNEL, + __BR_STP_MODE_MAX +}; + +#define BR_STP_MODE_MAX (__BR_STP_MODE_MAX - 1) + struct ifla_bridge_id { __u8 prio[2]; __u8 addr[6]; /* ETH_ALEN */ diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c index f7502e62dd357..a35ceae0a6f2c 100644 --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c @@ -518,6 +518,7 @@ void br_dev_setup(struct net_device *dev) ether_addr_copy(br->group_addr, eth_stp_addr); =20 br->stp_enabled =3D BR_NO_STP; + br->stp_mode =3D BR_STP_MODE_AUTO; br->group_fwd_mask =3D BR_GROUPFWD_DEFAULT; br->group_fwd_mask_required =3D BR_GROUPFWD_DEFAULT; =20 diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 0264730938f4b..6fd5386a1d646 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -1270,6 +1270,9 @@ static const struct nla_policy br_policy[IFLA_BR_MAX = + 1] =3D { NLA_POLICY_EXACT_LEN(sizeof(struct br_boolopt_multi)), [IFLA_BR_FDB_N_LEARNED] =3D { .type =3D NLA_REJECT }, [IFLA_BR_FDB_MAX_LEARNED] =3D { .type =3D NLA_U32 }, + [IFLA_BR_STP_MODE] =3D NLA_POLICY_RANGE(NLA_U32, + BR_STP_MODE_AUTO, + BR_STP_MODE_MAX), }; =20 static int br_changelink(struct net_device *brdev, struct nlattr *tb[], @@ -1306,6 +1309,23 @@ static int br_changelink(struct net_device *brdev, s= truct nlattr *tb[], return err; } =20 + if (data[IFLA_BR_STP_MODE]) { + u32 mode =3D nla_get_u32(data[IFLA_BR_STP_MODE]); + + if (mode !=3D br->stp_mode) { + bool stp_off =3D br->stp_enabled =3D=3D BR_NO_STP || + (data[IFLA_BR_STP_STATE] && + !nla_get_u32(data[IFLA_BR_STP_STATE])); + + if (!stp_off) { + NL_SET_ERR_MSG_MOD(extack, + "Can't change STP mode while STP is enabled"); + return -EBUSY; + } + } + br->stp_mode =3D mode; + } + if (data[IFLA_BR_STP_STATE]) { u32 stp_enabled =3D nla_get_u32(data[IFLA_BR_STP_STATE]); =20 @@ -1634,6 +1654,7 @@ static size_t br_get_size(const struct net_device *br= dev) nla_total_size(sizeof(u8)) + /* IFLA_BR_NF_CALL_ARPTABLES */ #endif nla_total_size(sizeof(struct br_boolopt_multi)) + /* IFLA_BR_MULTI= _BOOLOPT */ + nla_total_size(sizeof(u32)) + /* IFLA_BR_STP_MODE */ 0; } =20 @@ -1686,7 +1707,8 @@ static int br_fill_info(struct sk_buff *skb, const st= ruct net_device *brdev) nla_put(skb, IFLA_BR_MULTI_BOOLOPT, sizeof(bm), &bm) || nla_put_u32(skb, IFLA_BR_FDB_N_LEARNED, atomic_read(&br->fdb_n_learned)) || - nla_put_u32(skb, IFLA_BR_FDB_MAX_LEARNED, br->fdb_max_learned)) + nla_put_u32(skb, IFLA_BR_FDB_MAX_LEARNED, br->fdb_max_learned) || + nla_put_u32(skb, IFLA_BR_STP_MODE, br->stp_mode)) return -EMSGSIZE; =20 #ifdef CONFIG_BRIDGE_VLAN_FILTERING diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 6dbca845e625d..361a9b84451ec 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -523,6 +523,8 @@ struct net_bridge { unsigned char topology_change; unsigned char topology_change_detected; u16 root_port; + u8 stp_mode; + bool stp_helper_active; unsigned long max_age; unsigned long hello_time; unsigned long forward_delay; diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c index cc4b27ff1b088..28c1d3f7e22f6 100644 --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -149,7 +149,9 @@ static void br_stp_start(struct net_bridge *br) { int err =3D -ENOENT; =20 - if (net_eq(dev_net(br->dev), &init_net)) + /* AUTO mode: try bridge-stp helper in init_net only */ + if (br->stp_mode =3D=3D BR_STP_MODE_AUTO && + net_eq(dev_net(br->dev), &init_net)) err =3D br_stp_call_user(br, "start"); =20 if (err && err !=3D -ENOENT) @@ -162,8 +164,9 @@ static void br_stp_start(struct net_bridge *br) else if (br->bridge_forward_delay > BR_MAX_FORWARD_DELAY) __br_set_forward_delay(br, BR_MAX_FORWARD_DELAY); =20 - if (!err) { + if (br->stp_mode =3D=3D BR_STP_MODE_USER || !err) { br->stp_enabled =3D BR_USER_STP; + br->stp_helper_active =3D !err; br_debug(br, "userspace STP started\n"); } else { br->stp_enabled =3D BR_KERNEL_STP; @@ -180,12 +183,14 @@ static void br_stp_start(struct net_bridge *br) =20 static void br_stp_stop(struct net_bridge *br) { - int err; - if (br->stp_enabled =3D=3D BR_USER_STP) { - err =3D br_stp_call_user(br, "stop"); - if (err) - br_err(br, "failed to stop userspace STP (%d)\n", err); + if (br->stp_helper_active) { + int err =3D br_stp_call_user(br, "stop"); + + if (err) + br_err(br, "failed to stop userspace STP (%d)\n", err); + br->stp_helper_active =3D false; + } =20 /* To start timers on any ports left in blocking */ spin_lock_bh(&br->lock); --=20 2.43.0