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 503322AD00; Sun, 7 Jun 2026 10:20:44 +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=1780827645; cv=none; b=P3kAKi3aXYSSbjJMUN3U24mrvjXuY+liVVhAAxeC93eHj0kGE6CfjXVkzw4VuGxgfhn1o6htdA9OwrRvKLLZSLwMLdalFQX0+iHn05L4sD71cc9tqvC9XUcE/g5srdY+6PCJ7/6F5xu9ukjCciEIJysDkBcJis+9sPg6uNNRTiU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780827645; c=relaxed/simple; bh=hrpCifZjnyjEyGkhb0Slv1O6f/7jjzhMZxgKEmPSi3c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dXs2DOWj9tZgbcHL+harWOuqShqD1sB0nVy3lSD2CX5cJzuxUnTjy2KVim7rtvVPpSVMsAi2IxXtLL8gzV57+jDtgBXmlS681pZZYn4tjaLIglpMsqrTxxO9fJfePITt1lI9GRAJz7mA+EyGhZJLijKE1BhxGyK0l0fn/dDDmUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=eSMxfP1K; 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="eSMxfP1K" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9ABE71F00893; Sun, 7 Jun 2026 10:20:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780827644; bh=+6XBEoaklgE3Fb/th2jipRfbHOagvpqRxZLb8VgqlWY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eSMxfP1Kjeyc26W9WV359d2KUwsbmWPE0EqUQwlcQGX8GvhAMYZgQorCCXro9l8nm CHxsq9YwYxo2ZfIZUeF2+BdgEaxdMgujZTVLVxKeL8qTDeU6GRs3XDzUd8C3eLMF2Q FyBjpFhxI+DjhaMM4me30ltvlBP/unT8g8+gFv1o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jamal Hadi Salim , Cong Wang , Jiri Pirko , Sebastian Andrzej Siewior , Juri Lelli , Paolo Abeni , Sasha Levin Subject: [PATCH 6.12 075/307] net/sched: act_mirred: Move the recursion counter struct netdev_xmit Date: Sun, 7 Jun 2026 11:57:52 +0200 Message-ID: <20260607095730.518453501@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260607095727.647295505@linuxfoundation.org> References: <20260607095727.647295505@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sebastian Andrzej Siewior [ Upstream commit 7fe70c06a182a140be9996b02256d907e114479a ] mirred_nest_level is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Move mirred_nest_level to struct netdev_xmit as u8, provide wrappers. Cc: Jamal Hadi Salim Cc: Cong Wang Cc: Jiri Pirko Signed-off-by: Sebastian Andrzej Siewior Reviewed-by: Juri Lelli Link: https://patch.msgid.link/20250512092736.229935-11-bigeasy@linutronix.de Signed-off-by: Paolo Abeni Stable-dep-of: e80ad525fc7e ("net/sched: act_mirred: Fix return code in early mirred redirect error paths") Signed-off-by: Sasha Levin --- include/linux/netdevice_xmit.h | 3 +++ net/sched/act_mirred.c | 28 +++++++++++++++++++++++++--- 2 files changed, 28 insertions(+), 3 deletions(-) diff --git a/include/linux/netdevice_xmit.h b/include/linux/netdevice_xmit.h index 38325e07029685..848735b3a7c02d 100644 --- a/include/linux/netdevice_xmit.h +++ b/include/linux/netdevice_xmit.h @@ -8,6 +8,9 @@ struct netdev_xmit { #ifdef CONFIG_NET_EGRESS u8 skip_txqueue; #endif +#if IS_ENABLED(CONFIG_NET_ACT_MIRRED) + u8 sched_mirred_nest; +#endif }; #endif diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index b1b0049d7a0e9d..18d9378a9c1134 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -30,7 +30,29 @@ static LIST_HEAD(mirred_list); static DEFINE_SPINLOCK(mirred_list_lock); #define MIRRED_NEST_LIMIT 4 -static DEFINE_PER_CPU(unsigned int, mirred_nest_level); + +#ifndef CONFIG_PREEMPT_RT +static u8 tcf_mirred_nest_level_inc_return(void) +{ + return __this_cpu_inc_return(softnet_data.xmit.sched_mirred_nest); +} + +static void tcf_mirred_nest_level_dec(void) +{ + __this_cpu_dec(softnet_data.xmit.sched_mirred_nest); +} + +#else +static u8 tcf_mirred_nest_level_inc_return(void) +{ + return current->net_xmit.sched_mirred_nest++; +} + +static void tcf_mirred_nest_level_dec(void) +{ + current->net_xmit.sched_mirred_nest--; +} +#endif static bool tcf_mirred_is_act_redirect(int action) { @@ -423,7 +445,7 @@ TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, int m_eaction; u32 blockid; - nest_level = __this_cpu_inc_return(mirred_nest_level); + nest_level = tcf_mirred_nest_level_inc_return(); if (unlikely(nest_level > MIRRED_NEST_LIMIT)) { net_warn_ratelimited("Packet exceeded mirred recursion limit on dev %s\n", netdev_name(skb->dev)); @@ -454,7 +476,7 @@ TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, retval); dec_nest_level: - __this_cpu_dec(mirred_nest_level); + tcf_mirred_nest_level_dec(); return retval; } -- 2.53.0