From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3D98E6A352; Tue, 14 May 2024 10:44:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715683461; cv=none; b=VIC8nlT1cjOlBRvAYlWaP6n09DJBdTQZWnAeJK6yYEl1hSD6gW8RLMl1IhPHrSW/Yr40Phsp4ywPSXmrm13lyT6LlC6dHZhesgEKOAroA5SdkGjgi7dnq/pjuRm9cOBW3p7LqqRWWxFuloKy0g6WYjBFUqfrghEsaZBwILXy2wM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715683461; c=relaxed/simple; bh=DnPKGkTaxBzpVP0dqcYwxdNwqt5JqAYEdW14RYs2pFo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fQG9/L2W6YNRMOb2nnVGEpLDvq4aT9aC38+jp1Veq+C9mV0nyKAcw1+OFomGTvNbZ38LApzyhcgj064NYbY/nyfQNKNb6CFpQS/ORfpQd9iNOrX4+Il7VY+iRzVTGDtxuxi3nTSnh8ZdgWNqL0zSaNwDyCu8psz5bR5FFfud5Eg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=EDOYY7+m; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="EDOYY7+m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2384BC2BD10; Tue, 14 May 2024 10:44:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1715683461; bh=DnPKGkTaxBzpVP0dqcYwxdNwqt5JqAYEdW14RYs2pFo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EDOYY7+m4961pbKivs847VsIBhKa7EdD02zr3zPh8sq354a9fe+c3R50od0o9BbIb PQgFQrMNepWBP5q5M4Tfm6NBNTocqqwtlYMGQT7cJ68ORTUwClsFLYQIipoT6sWe+o w46JgWTU5iUK0mZyMD40o0XJrxSY2CBN14yNeNO4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , "David S. Miller" , Sasha Levin Subject: [PATCH 6.8 221/336] net-sysfs: convert dev->operstate reads to lockless ones Date: Tue, 14 May 2024 12:17:05 +0200 Message-ID: <20240514101046.959080444@linuxfoundation.org> X-Mailer: git-send-email 2.45.0 In-Reply-To: <20240514101038.595152603@linuxfoundation.org> References: <20240514101038.595152603@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit 004d138364fd10dd5ff8ceb54cfdc2d792a7b338 ] operstate_show() can omit dev_base_lock acquisition only to read dev->operstate. Annotate accesses to dev->operstate. Writers still acquire dev_base_lock for mutual exclusion. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Stable-dep-of: 4893b8b3ef8d ("hsr: Simplify code for announcing HSR nodes timer setup") Signed-off-by: Sasha Levin --- net/bridge/br_netlink.c | 3 ++- net/core/link_watch.c | 4 ++-- net/core/net-sysfs.c | 4 +--- net/core/rtnetlink.c | 4 ++-- net/hsr/hsr_device.c | 10 +++++----- net/ipv6/addrconf.c | 2 +- 6 files changed, 13 insertions(+), 14 deletions(-) diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index d415833fce91f..f17dbac7d8284 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -455,7 +455,8 @@ static int br_fill_ifinfo(struct sk_buff *skb, u32 filter_mask, const struct net_device *dev, bool getlink) { - u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN; + u8 operstate = netif_running(dev) ? READ_ONCE(dev->operstate) : + IF_OPER_DOWN; struct nlattr *af = NULL; struct net_bridge *br; struct ifinfomsg *hdr; diff --git a/net/core/link_watch.c b/net/core/link_watch.c index 429571c258da7..1b93e054c9a3c 100644 --- a/net/core/link_watch.c +++ b/net/core/link_watch.c @@ -67,7 +67,7 @@ static void rfc2863_policy(struct net_device *dev) { unsigned char operstate = default_operstate(dev); - if (operstate == dev->operstate) + if (operstate == READ_ONCE(dev->operstate)) return; write_lock(&dev_base_lock); @@ -87,7 +87,7 @@ static void rfc2863_policy(struct net_device *dev) break; } - dev->operstate = operstate; + WRITE_ONCE(dev->operstate, operstate); write_unlock(&dev_base_lock); } diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index a09d507c5b03d..676048ae11831 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -318,11 +318,9 @@ static ssize_t operstate_show(struct device *dev, const struct net_device *netdev = to_net_dev(dev); unsigned char operstate; - read_lock(&dev_base_lock); - operstate = netdev->operstate; + operstate = READ_ONCE(netdev->operstate); if (!netif_running(netdev)) operstate = IF_OPER_DOWN; - read_unlock(&dev_base_lock); if (operstate >= ARRAY_SIZE(operstates)) return -EINVAL; /* should not happen */ diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 4e4e6c7399109..95e62235b5410 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -875,9 +875,9 @@ static void set_operstate(struct net_device *dev, unsigned char transition) break; } - if (dev->operstate != operstate) { + if (READ_ONCE(dev->operstate) != operstate) { write_lock(&dev_base_lock); - dev->operstate = operstate; + WRITE_ONCE(dev->operstate, operstate); write_unlock(&dev_base_lock); netdev_state_change(dev); } diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c index 9d71b66183daf..be0e43f46556e 100644 --- a/net/hsr/hsr_device.c +++ b/net/hsr/hsr_device.c @@ -31,8 +31,8 @@ static bool is_slave_up(struct net_device *dev) static void __hsr_set_operstate(struct net_device *dev, int transition) { write_lock(&dev_base_lock); - if (dev->operstate != transition) { - dev->operstate = transition; + if (READ_ONCE(dev->operstate) != transition) { + WRITE_ONCE(dev->operstate, transition); write_unlock(&dev_base_lock); netdev_state_change(dev); } else { @@ -78,14 +78,14 @@ static void hsr_check_announce(struct net_device *hsr_dev, hsr = netdev_priv(hsr_dev); - if (hsr_dev->operstate == IF_OPER_UP && old_operstate != IF_OPER_UP) { + if (READ_ONCE(hsr_dev->operstate) == IF_OPER_UP && old_operstate != IF_OPER_UP) { /* Went up */ hsr->announce_count = 0; mod_timer(&hsr->announce_timer, jiffies + msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL)); } - if (hsr_dev->operstate != IF_OPER_UP && old_operstate == IF_OPER_UP) + if (READ_ONCE(hsr_dev->operstate) != IF_OPER_UP && old_operstate == IF_OPER_UP) /* Went down */ del_timer(&hsr->announce_timer); } @@ -100,7 +100,7 @@ void hsr_check_carrier_and_operstate(struct hsr_priv *hsr) /* netif_stacked_transfer_operstate() cannot be used here since * it doesn't set IF_OPER_LOWERLAYERDOWN (?) */ - old_operstate = master->dev->operstate; + old_operstate = READ_ONCE(master->dev->operstate); has_carrier = hsr_check_carrier(master); hsr_set_operstate(master, has_carrier); hsr_check_announce(master->dev, old_operstate); diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 37d48aa073c3c..775f51cbc539b 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -6015,7 +6015,7 @@ static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev, (dev->ifindex != dev_get_iflink(dev) && nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) || nla_put_u8(skb, IFLA_OPERSTATE, - netif_running(dev) ? dev->operstate : IF_OPER_DOWN)) + netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN)) goto nla_put_failure; protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO); if (!protoinfo) -- 2.43.0