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 2A1A946D541; Tue, 21 Jul 2026 15:43:18 +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=1784648599; cv=none; b=JLbo+3WxgQ7EAUAcqVZvGz44ndi6d78AOpOihXQbWuPR5TeSV0Ftqg/QOYBAp/tWoI3aJgniykmc70uG8draeF7MMy1NDuheKTquRiw/vjsCjD53uiTuaME8Z7mkRKikp+cBYmaadWMXF8zxtQZsY7AgYGbY4i9EmxdnrIkD8s4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784648599; c=relaxed/simple; bh=lBCMpwjHJtj3ooPO3cD7XvheuHnkSqr/1Z4EK0BopFU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RnHp/niU1EPO3/Z+Vgr7aGxHBKtFKBW+IzjNZaOJ/00oLJIt9XO81n0yDdffuz2sqQ6/ueqwOnur8hbdJYVPAIFV4sLEM4VbzVa1h5lUTVy+2Wdsu6zWdkXLx4EjU2lx8e9sSXsixJpHq0XfLYbVwWsoVrs6GDOKmM7RAgrfv6Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UiEFJXFZ; 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="UiEFJXFZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8B5921F000E9; Tue, 21 Jul 2026 15:43:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784648598; bh=/D0gTo13Qo0YRJ8WP0X8eQJ3Hu6CpnAyepxNv1NkwLA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=UiEFJXFZy7xA5QVDKpkAUZ4xYTSU4PxGPSQxWmFoTwvtXfIByZSyQSSA8Nur5gZbS qBRRHCqxjQ55BfCUZLTjKU5t/kygUuCroPWJapdVA9kc3HwrgrhK0iQzy9ZAA8tXCf nFNcV5ySEEULeqVQrNYbywyhEUtHCAhm+UJZejGY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eric Dumazet , Jakub Kicinski , Sasha Levin Subject: [PATCH 7.1 0259/2077] net/sched: sch_drr: annotate data-races around cl->deficit Date: Tue, 21 Jul 2026 16:58:52 +0200 Message-ID: <20260721152558.788846469@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152552.646164743@linuxfoundation.org> References: <20260721152552.646164743@linuxfoundation.org> User-Agent: quilt/0.69 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 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit c67b104fd7982162885c5e43057ca761006748e2 ] drr_dump_class_stats() runs without qdisc spinlock held. Add missing READ_ONCE()/WRITE_ONCE() annotations around cl->deficit. Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260519094618.2632073-2-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_drr.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/sched/sch_drr.c b/net/sched/sch_drr.c index 925fa0cfd730ce..2eedd3a4322ad5 100644 --- a/net/sched/sch_drr.c +++ b/net/sched/sch_drr.c @@ -270,7 +270,7 @@ static int drr_dump_class_stats(struct Qdisc *sch, unsigned long arg, memset(&xstats, 0, sizeof(xstats)); if (qlen) - xstats.deficit = cl->deficit; + xstats.deficit = READ_ONCE(cl->deficit); if (gnet_stats_copy_basic(d, NULL, &cl->bstats, true) < 0 || gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || @@ -362,7 +362,7 @@ static int drr_enqueue(struct sk_buff *skb, struct Qdisc *sch, if (!cl_is_active(cl)) { list_add_tail(&cl->alist, &q->active); - cl->deficit = cl->quantum; + WRITE_ONCE(cl->deficit, cl->quantum); } sch->qstats.backlog += len; @@ -389,7 +389,7 @@ static struct sk_buff *drr_dequeue(struct Qdisc *sch) len = qdisc_pkt_len(skb); if (len <= cl->deficit) { - cl->deficit -= len; + WRITE_ONCE(cl->deficit, cl->deficit - len); skb = qdisc_dequeue_peeked(cl->qdisc); if (unlikely(skb == NULL)) goto out; @@ -403,7 +403,7 @@ static struct sk_buff *drr_dequeue(struct Qdisc *sch) return skb; } - cl->deficit += cl->quantum; + WRITE_ONCE(cl->deficit, cl->deficit + cl->quantum); list_move_tail(&cl->alist, &q->active); } out: -- 2.53.0