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 7B3082F90E0; Sat, 30 May 2026 18:11:54 +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=1780164715; cv=none; b=ok8zHKs1u3MOFXG8qihppGPue8EKOsEB8TdSYn7ebEJLm70F0UCBka+dFLkRO7ixJYC9TwgTuNvGRzLfVP+jD4YQU5LxdZu5Im36o3aWQP+3YIEh998I/oTcI1o1c7nU6lqurZG8XW1KygN4XLue2Z6lh3RD6apyB/4dlFlpxz0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780164715; c=relaxed/simple; bh=DBinf9gI/AQ6dI9CXumfyO6haZn2cVJqzPKrGox8JJE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Jbx8T2Qopfu2ojL9Z6kcehqv6O2CQzskaZDjkkwdM0Pi3hqzif0UyTtbHegEPwQbXy/fkAluieH543XYa1AG9pGV7C1GA6GXMPW9M7JeygvVrFXxq8hKiZ45UvI9y1o/pbQTQjRKrxjRnOKUJOJ44GziYcBPBGhbC47VFOkkpow= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ox5QX5G1; 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="ox5QX5G1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBE561F00893; Sat, 30 May 2026 18:11:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780164714; bh=wqIh99atCrVMgr2hp4x5s9HlL5sdpEL8MRzWLP8q7H8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ox5QX5G1cIhAP1/phNrR53GQuCyc1tcox+UEFtKzZ5n6NTM/8zI05uPYij4w0pGCs iJohLwHqMhwi2spjYArDWQDVKE3VwPmpWjxb7Fk2uJX2o9xH5menVSt/sWjx/b51kO 8XIFfN+mS5sO2kHGMqE43zwHBknrCURRI4HDoq/k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Jamal Hadi Salim , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 620/776] net/sched: sch_fq_pie: annotate data-races in fq_pie_dump_stats() Date: Sat, 30 May 2026 18:05:34 +0200 Message-ID: <20260530160256.011414801@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160240.228940103@linuxfoundation.org> References: <20260530160240.228940103@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: Eric Dumazet [ Upstream commit 59b145771c7982cfe9020d4e9e22da92d6b5ae31 ] fq_codel_dump_stats() acquires the qdisc spinlock a bit too late. Move this acquisition before we fill tc_fq_pie_xstats with live data. Alternative would be to add READ_ONCE() and WRITE_ONCE() annotations, but the spinlock is needed anyway to scan q->new_flows and q->old_flows. Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Signed-off-by: Eric Dumazet Reviewed-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260423063527.2568262-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_fq_pie.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/sched/sch_fq_pie.c b/net/sched/sch_fq_pie.c index 30259c8756451..910efc0630a14 100644 --- a/net/sched/sch_fq_pie.c +++ b/net/sched/sch_fq_pie.c @@ -499,18 +499,19 @@ static int fq_pie_dump(struct Qdisc *sch, struct sk_buff *skb) static int fq_pie_dump_stats(struct Qdisc *sch, struct gnet_dump *d) { struct fq_pie_sched_data *q = qdisc_priv(sch); - struct tc_fq_pie_xstats st = { - .packets_in = q->stats.packets_in, - .overlimit = q->stats.overlimit, - .overmemory = q->overmemory, - .dropped = q->stats.dropped, - .ecn_mark = q->stats.ecn_mark, - .new_flow_count = q->new_flow_count, - .memory_usage = q->memory_usage, - }; + struct tc_fq_pie_xstats st = { 0 }; struct list_head *pos; sch_tree_lock(sch); + + st.packets_in = q->stats.packets_in; + st.overlimit = q->stats.overlimit; + st.overmemory = q->overmemory; + st.dropped = q->stats.dropped; + st.ecn_mark = q->stats.ecn_mark; + st.new_flow_count = q->new_flow_count; + st.memory_usage = q->memory_usage; + list_for_each(pos, &q->new_flows) st.new_flows_len++; -- 2.53.0