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 18300471413; Tue, 21 Jul 2026 20:28:19 +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=1784665701; cv=none; b=plxLr1XjdyVYIllp4elAApHA/uREx3jp8DIKQo4k6beI4Yzkc8Jw0BjV7oAPakr8TFwBBMtMmJwpw4xKJpNktg7nOG6o3fbxQJJPr0cTVc0SnnGhCnqfZc8TmtmYTExDLgmAMzqiCijssWQu7q3zkwmXtccVfxcx7wdgkO6IkLs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784665701; c=relaxed/simple; bh=U2UKAVYXDXYDxbkJi2XvKm+C9dTBdCAZNOj8Vx64eaA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=H49uZmXwVWNRzKIAzD9IWUHPdmUMxYqmYp+VxAmqejHX8x3zLCo8cxVcXSujz9hNTnHdg3GZhXBdXfgZ0SGtP4khxDr1GaOpddibQd4rrB/Ahmmn7NHsdCDm7uWTgFUTAep5ZJ8Q9ZXQHPBqz9vJ7iOZFCcRr9kJFgYH0XlR7Go= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SpAt5c+j; 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="SpAt5c+j" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19FBA1F00A3A; Tue, 21 Jul 2026 20:28:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784665697; bh=PUazpM3a4pgUbb5zRwpuwlHQMnG9fg08dgveYwzaW9s=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SpAt5c+jcymVEE2FI/7okROEYgmZQEjkU+lMWZFd/5WnmXTnCO735Ic5IjiuCAn8i c30PTbsWP1GFwPztatojY4GYNfM8gPAsF+KZGRz3uPR18nSMFaVkSciPq6xbh9kAuq gVvp4ZW0jNIyAooQf3ES4ixG1a/6Ve9q/wQBXEgw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.6 0401/1266] net/sched: sch_hfsc: annotate data-races in hfsc_dump_class_stats() Date: Tue, 21 Jul 2026 17:13:58 +0200 Message-ID: <20260721152450.804535558@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152441.786066624@linuxfoundation.org> References: <20260721152441.786066624@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit e300c7d470ad2726d6abf7d11b31b5d9912d9cf0 ] hfsc_dump_class_stats() runs without qdisc spinlock being held. Add READ_ONCE()/WRITE_ONCE() annotations around: - cl->level - cl->cl_vtperiod - cl->cl_total - cl->cl_cumul Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet Reviewed-by: Toke Høiland-Jørgensen Link: https://patch.msgid.link/20260513080853.1383975-4-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_hfsc.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c index 1ac51d02499195..11ae998cda3a85 100644 --- a/net/sched/sch_hfsc.c +++ b/net/sched/sch_hfsc.c @@ -715,7 +715,7 @@ init_vf(struct hfsc_class *cl, unsigned int len) rtsc_min(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); cl->cl_vtadj = 0; - cl->cl_vtperiod++; /* increment vt period */ + WRITE_ONCE(cl->cl_vtperiod, cl->cl_vtperiod + 1); /* increment vt period */ cl->cl_parentperiod = cl->cl_parent->cl_vtperiod; if (cl->cl_parent->cl_nactive == 0) cl->cl_parentperiod++; @@ -757,7 +757,7 @@ update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time) go_passive = 1; for (; cl->cl_parent != NULL; cl = cl->cl_parent) { - cl->cl_total += len; + WRITE_ONCE(cl->cl_total, cl->cl_total + len); if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0) continue; @@ -847,7 +847,7 @@ hfsc_adjust_levels(struct hfsc_class *cl) if (p->level >= level) level = p->level + 1; } - cl->level = level; + WRITE_ONCE(cl->level, level); } while ((cl = cl->cl_parent) != NULL); } @@ -1337,10 +1337,10 @@ hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg, __u32 qlen; qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog); - xstats.level = cl->level; - xstats.period = cl->cl_vtperiod; - xstats.work = cl->cl_total; - xstats.rtwork = cl->cl_cumul; + xstats.level = READ_ONCE(cl->level); + xstats.period = READ_ONCE(cl->cl_vtperiod); + xstats.work = READ_ONCE(cl->cl_total); + xstats.rtwork = READ_ONCE(cl->cl_cumul); if (gnet_stats_copy_basic(d, NULL, &cl->bstats, true) < 0 || gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || @@ -1453,15 +1453,15 @@ hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt, static void hfsc_reset_class(struct hfsc_class *cl) { - cl->cl_total = 0; - cl->cl_cumul = 0; + WRITE_ONCE(cl->cl_total, 0); + WRITE_ONCE(cl->cl_cumul, 0); cl->cl_d = 0; cl->cl_e = 0; cl->cl_vt = 0; cl->cl_vtadj = 0; cl->cl_cvtmin = 0; cl->cl_cvtoff = 0; - cl->cl_vtperiod = 0; + WRITE_ONCE(cl->cl_vtperiod, 0); cl->cl_parentperiod = 0; cl->cl_f = 0; cl->cl_myf = 0; @@ -1627,7 +1627,7 @@ hfsc_dequeue(struct Qdisc *sch) bstats_update(&cl->bstats, skb); update_vf(cl, qdisc_pkt_len(skb), cur_time); if (realtime) - cl->cl_cumul += qdisc_pkt_len(skb); + WRITE_ONCE(cl->cl_cumul, cl->cl_cumul + qdisc_pkt_len(skb)); if (cl->cl_flags & HFSC_RSC) { if (cl->qdisc->q.qlen != 0) { -- 2.53.0