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 2794744AB98; Tue, 21 Jul 2026 21:20:16 +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=1784668817; cv=none; b=SdZItsxKSAKh9C3UOiL1yIiIuu8rSQ7DfzWkk1xf2n+kfBpTNBrk//isafgHROkwGJlsZ9fb9p7psR2NLU/iBPcITjGfGbRL9xSzYMINPCumXqdzL/VmHZpOorgJ6fjIT7d9qBfqyywAGFFN6gZlDE7etR8F51I3jtNbVcCRch8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784668817; c=relaxed/simple; bh=9VbHSIGbRF1hxe0gZ3/CEpWyzzqZemHnESWtudBhwlg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PzitYDqJsMQaf85SZBgP25eqrB8/1u/M7nbGhkCldYc2DsZxhCAR9ZhyZkpZR4TLi/Cv0GIJn7lpVpnLrW7sY7e8svaRweUm9pbWN9NiVh+BZLyyWAYrf1rTun1gMMOSakYV6Ij7HTUSYs9QBQjDspAKSLmty58emiPOqApXmiU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=aZx7pOg3; 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="aZx7pOg3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 889F71F000E9; Tue, 21 Jul 2026 21:20:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784668816; bh=XhH+A8Mfz/8fmp6OxRdyeabrhaq7B1KtBd7OnLSYDrM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=aZx7pOg3aKXkuSA3lzk8oP7XQVJ7zGYOZIMDtJxKaO/2LB9Pu0cRk4IXGM2mr4beq AA6pwLkuykni/hiGladyxpSlgzIsAD1St9D3cB/nIrBtr9ABBkn+7vIjFku24B8hZn rmIwK++cbiESmvhLr8ml/Cq4ARMOJ7C8jfJ6f+hQ= 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 6.1 0318/1067] net/sched: sch_drr: annotate data-races around cl->deficit Date: Tue, 21 Jul 2026 17:15:19 +0200 Message-ID: <20260721152431.705948234@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152424.521567757@linuxfoundation.org> References: <20260721152424.521567757@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 6.1-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 3aee041c7bdbaa..f6048a2eddce4e 100644 --- a/net/sched/sch_drr.c +++ b/net/sched/sch_drr.c @@ -269,7 +269,7 @@ 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 || @@ -361,7 +361,7 @@ 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; @@ -388,7 +388,7 @@ 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; @@ -402,7 +402,7 @@ 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