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 C625C3F1ADC; Wed, 20 May 2026 17:46:01 +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=1779299162; cv=none; b=FT2yfjfcSXei+CN5TIFsJWelr6ZUo1uEG9kGewdivMsKJpu2BL197GKuGX4rw2clJ6YYEQMYK0OuyuM1vlcCi7z0bHz2/QtF2t69D+kwYOkhBFUb8w7/pyVBbzk2rsMMtVK6xH/nYI7Msmrl5IX+jl4lOaFl/fWHfy9RBtv/4N8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779299162; c=relaxed/simple; bh=Zn9wzP4HuslQSXPDHpQRfDvcet3AfrHkZzyU/p1c0zA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cm4ooRctsgIM/G4xNd/Dy1Mbsf4Kn9dUTzx4NkQjXPS6cX04o4w0Zh7xt7S9EDEhsgSWSf/k9aqsvWlo41CY2Sl31fbjG9jp/rzsT9yVc5wnYTUfY16n4/3tX1CJb+PdTELO3rck1J18KZVpHkO3kRaeu3WhfCPllffptxshFsE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JALEm6ge; 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="JALEm6ge" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 361281F000E9; Wed, 20 May 2026 17:46:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779299161; bh=cXOY1TNRcldTLUBh8qUgdnqZQd0/8AtQaVq5x8Pc33E=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=JALEm6ge01j/Jxv/UprhHC/FhkA6VUK4v88vDDFJnBi6BVZp26bP+OQV7S7G1xwDv o53kr7rItnw1K4nYxalNaBqY+c27b1B0+ngW2dGXuzJmHz9Iitgvgd/UvltUSBLn9o UCngSfwJlnVYbbClL2v4htV/1hn1qXo6iu6FJk24= 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 6.18 686/957] net_sched: sch_hhf: annotate data-races in hhf_dump_stats() Date: Wed, 20 May 2026 18:19:29 +0200 Message-ID: <20260520162149.417384687@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet [ Upstream commit a6edf2cd4156b71e07258876b7626692e158f7e8 ] hhf_dump_stats() only runs with RTNL held, reading fields that can be changed in qdisc fast path. Add READ_ONCE()/WRITE_ONCE() annotations. Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet Reviewed-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260421143349.4052215-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sched/sch_hhf.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/sched/sch_hhf.c b/net/sched/sch_hhf.c index 2d4855e28a286..81c3a388c9437 100644 --- a/net/sched/sch_hhf.c +++ b/net/sched/sch_hhf.c @@ -198,7 +198,8 @@ static struct hh_flow_state *seek_list(const u32 hash, return NULL; list_del(&flow->flowchain); kfree(flow); - q->hh_flows_current_cnt--; + WRITE_ONCE(q->hh_flows_current_cnt, + q->hh_flows_current_cnt - 1); } else if (flow->hash_id == hash) { return flow; } @@ -226,7 +227,7 @@ static struct hh_flow_state *alloc_new_hh(struct list_head *head, } if (q->hh_flows_current_cnt >= q->hh_flows_limit) { - q->hh_flows_overlimit++; + WRITE_ONCE(q->hh_flows_overlimit, q->hh_flows_overlimit + 1); return NULL; } /* Create new entry. */ @@ -234,7 +235,7 @@ static struct hh_flow_state *alloc_new_hh(struct list_head *head, if (!flow) return NULL; - q->hh_flows_current_cnt++; + WRITE_ONCE(q->hh_flows_current_cnt, q->hh_flows_current_cnt + 1); INIT_LIST_HEAD(&flow->flowchain); list_add_tail(&flow->flowchain, head); @@ -309,7 +310,7 @@ static enum wdrr_bucket_idx hhf_classify(struct sk_buff *skb, struct Qdisc *sch) return WDRR_BUCKET_FOR_NON_HH; flow->hash_id = hash; flow->hit_timestamp = now; - q->hh_flows_total_cnt++; + WRITE_ONCE(q->hh_flows_total_cnt, q->hh_flows_total_cnt + 1); /* By returning without updating counters in q->hhf_arrays, * we implicitly implement "shielding" (see Optimization O1). @@ -403,7 +404,7 @@ static int hhf_enqueue(struct sk_buff *skb, struct Qdisc *sch, return NET_XMIT_SUCCESS; prev_backlog = sch->qstats.backlog; - q->drop_overlimit++; + WRITE_ONCE(q->drop_overlimit, q->drop_overlimit + 1); /* Return Congestion Notification only if we dropped a packet from this * bucket. */ @@ -687,10 +688,10 @@ static int hhf_dump_stats(struct Qdisc *sch, struct gnet_dump *d) { struct hhf_sched_data *q = qdisc_priv(sch); struct tc_hhf_xstats st = { - .drop_overlimit = q->drop_overlimit, - .hh_overlimit = q->hh_flows_overlimit, - .hh_tot_count = q->hh_flows_total_cnt, - .hh_cur_count = q->hh_flows_current_cnt, + .drop_overlimit = READ_ONCE(q->drop_overlimit), + .hh_overlimit = READ_ONCE(q->hh_flows_overlimit), + .hh_tot_count = READ_ONCE(q->hh_flows_total_cnt), + .hh_cur_count = READ_ONCE(q->hh_flows_current_cnt), }; return gnet_stats_copy_app(d, &st, sizeof(st)); -- 2.53.0