From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 5C8663A6F09; Sat, 12 Sep 2026 19:11:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789240323; cv=none; b=lUYUNmbbg8dFrz+G7EK5FfYxB7D/CagCFuPlEEA0712OJDD/cjMCc9uHMPgUqK0+7M/NFRGPdiDQANq/brK9D7cyt7N1+oqFV9mI/pwRF8d0LAl400coGjxen9ThnRG+nb05goARchGHhOr2qqIWwan1vRntFcXvHd2uDxhkOXA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789240323; c=relaxed/simple; bh=O0vT5zfLjKoIl1hj+WtSTCSnx42EyJBqOLOvjKwNKyQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GDbc8WY/sN5mBKXhoGq9BPqScgIX0b/PNjQm9M2O2ldSlx0KwB8HRniGrfdj0ZPE1a4AQb3xnZCdSCmeLj9VBRZ6WFbGDFcjbwyktKT7AefqpyFYXFEJYrcpyn4n6eoxiE5U2VOXQGDII8S36Yl//no6qCPH0CB/vA3GWpnPm58= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ox0DjXnX; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ox0DjXnX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EA9021F000FF; Sat, 12 Sep 2026 19:11:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789240319; bh=5voZ3nFJgR/fe7hCmTfDzyjsC5/usqllQFZM6qFXKLs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ox0DjXnXGgokMxNw79Lulpnuv6jRV/XqFf0pq/rcUWtC4GXczE0h9gDqqfWUTursQ YQZUuoxIt1XMAKgQ1BmJeEMwI8Xdz/3xrT8TRTxCMdwfeuhvZdqtR4i97QHB1KiFlA RvvmIMyDQpLB6bfLyTCDosi2UE6gEg6QDUnn/szU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sebastian Andrzej Siewior , Kurt Kanzenbach , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 843/935] hsr: Use a single struct for self_node. Date: Sat, 12 Sep 2026 09:04:33 +0200 Message-ID: <20260912065546.162646256@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior [ Upstream commit 20d3c1e9b861b85e1a774e1876d6adeeb0251fc3 ] self_node_db is a list_head with one entry of struct hsr_node. The purpose is to hold the two MAC addresses of the node itself. It is convenient to recycle the structure. However having a list_head and fetching always the first entry is not really optimal. Created a new data strucure contaning the two MAC addresses named hsr_self_node. Access that structure like an RCU protected pointer so it can be replaced on the fly without blocking the reader. Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Kurt Kanzenbach Signed-off-by: Jakub Kicinski Stable-dep-of: 7f16289b91eb ("net: hsr: free learned nodes on device setup failure") Signed-off-by: Sasha Levin --- net/hsr/hsr_device.c | 1 - net/hsr/hsr_framereg.c | 63 +++++++++++++++++++----------------------- net/hsr/hsr_main.h | 8 +++++- 3 files changed, 35 insertions(+), 37 deletions(-) diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c index 0d7550f7498e1..93ccd67717cb1 100644 --- a/net/hsr/hsr_device.c +++ b/net/hsr/hsr_device.c @@ -637,7 +637,6 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2], hsr = netdev_priv(hsr_dev); INIT_LIST_HEAD(&hsr->ports); INIT_LIST_HEAD(&hsr->node_db); - INIT_LIST_HEAD(&hsr->self_node_db); spin_lock_init(&hsr->list_lock); eth_hw_addr_set(hsr_dev, slave[0]->dev_addr); diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c index 0b3d9dfbe6d6c..b40b45331a81f 100644 --- a/net/hsr/hsr_framereg.c +++ b/net/hsr/hsr_framereg.c @@ -40,21 +40,22 @@ static bool seq_nr_after(u16 a, u16 b) bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr) { - struct hsr_node *node; + struct hsr_self_node *sn; + bool ret = false; - node = list_first_or_null_rcu(&hsr->self_node_db, struct hsr_node, - mac_list); - if (!node) { + rcu_read_lock(); + sn = rcu_dereference(hsr->self_node); + if (!sn) { WARN_ONCE(1, "HSR: No self node\n"); - return false; + goto out; } - if (ether_addr_equal(addr, node->macaddress_A)) - return true; - if (ether_addr_equal(addr, node->macaddress_B)) - return true; - - return false; + if (ether_addr_equal(addr, sn->macaddress_A) || + ether_addr_equal(addr, sn->macaddress_B)) + ret = true; +out: + rcu_read_unlock(); + return ret; } /* Search for mac entry. Caller must hold rcu read lock. @@ -72,50 +73,42 @@ static struct hsr_node *find_node_by_addr_A(struct list_head *node_db, return NULL; } -/* Helper for device init; the self_node_db is used in hsr_rcv() to recognize +/* Helper for device init; the self_node is used in hsr_rcv() to recognize * frames from self that's been looped over the HSR ring. */ int hsr_create_self_node(struct hsr_priv *hsr, unsigned char addr_a[ETH_ALEN], unsigned char addr_b[ETH_ALEN]) { - struct list_head *self_node_db = &hsr->self_node_db; - struct hsr_node *node, *oldnode; + struct hsr_self_node *sn, *old; - node = kmalloc(sizeof(*node), GFP_KERNEL); - if (!node) + sn = kmalloc(sizeof(*sn), GFP_KERNEL); + if (!sn) return -ENOMEM; - ether_addr_copy(node->macaddress_A, addr_a); - ether_addr_copy(node->macaddress_B, addr_b); + ether_addr_copy(sn->macaddress_A, addr_a); + ether_addr_copy(sn->macaddress_B, addr_b); spin_lock_bh(&hsr->list_lock); - oldnode = list_first_or_null_rcu(self_node_db, - struct hsr_node, mac_list); - if (oldnode) { - list_replace_rcu(&oldnode->mac_list, &node->mac_list); - spin_unlock_bh(&hsr->list_lock); - kfree_rcu(oldnode, rcu_head); - } else { - list_add_tail_rcu(&node->mac_list, self_node_db); - spin_unlock_bh(&hsr->list_lock); - } + old = rcu_replace_pointer(hsr->self_node, sn, + lockdep_is_held(&hsr->list_lock)); + spin_unlock_bh(&hsr->list_lock); + if (old) + kfree_rcu(old, rcu_head); return 0; } void hsr_del_self_node(struct hsr_priv *hsr) { - struct list_head *self_node_db = &hsr->self_node_db; - struct hsr_node *node; + struct hsr_self_node *old; spin_lock_bh(&hsr->list_lock); - node = list_first_or_null_rcu(self_node_db, struct hsr_node, mac_list); - if (node) { - list_del_rcu(&node->mac_list); - kfree_rcu(node, rcu_head); - } + old = rcu_replace_pointer(hsr->self_node, NULL, + lockdep_is_held(&hsr->list_lock)); spin_unlock_bh(&hsr->list_lock); + if (old) + kfree_rcu(old, rcu_head); } void hsr_del_nodes(struct list_head *node_db) diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h index 5c0e5f6d1eda1..cdbc61a006386 100644 --- a/net/hsr/hsr_main.h +++ b/net/hsr/hsr_main.h @@ -192,11 +192,17 @@ struct hsr_proto_ops { void (*update_san_info)(struct hsr_node *node, bool is_sup); }; +struct hsr_self_node { + unsigned char macaddress_A[ETH_ALEN]; + unsigned char macaddress_B[ETH_ALEN]; + struct rcu_head rcu_head; +}; + struct hsr_priv { struct rcu_head rcu_head; struct list_head ports; struct list_head node_db; /* Known HSR nodes */ - struct list_head self_node_db; /* MACs of slaves */ + struct hsr_self_node __rcu *self_node; /* MACs of slaves */ struct timer_list announce_timer; /* Supervision frame dispatch */ struct timer_list prune_timer; int announce_count; -- 2.53.0