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Date: Fri, 8 Aug 2025 13:29:15 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: "He, Guocai (CN)" <Guocai.He.CN@windriver.com>
Cc: Lion Ackermann <nnamrec@gmail.com>, "netdev@vger.kernel.org"
 <netdev@vger.kernel.org>, "linux-kernel@vger.kernel.org"
 <linux-kernel@vger.kernel.org>, "ovs-discuss@openvswitch.org"
 <ovs-discuss@openvswitch.org>
Subject: Re: [netdev] htb_qlen_notify warning triggered after
 qdisc_tree_reduce_backlog change
Message-ID: <20250808132915.7f6c8678@kernel.org>
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On Wed, 6 Aug 2025 08:29:34 +0000 He, Guocai (CN) wrote:
> ### Environment
> - Kernel version: 5.15.189-rt76-yocto-preempt-rt
> - Open vSwitch version: 2.17.9
    
> ### Issue
> After applying the QoS configuration, the following warning appears in dmesg:
> [73591.168117] WARNING: CPU: 6 PID: 61296 at net/sched/sch_htb.c:609 htb_qlen_notify+0x3a/0x40 [sch_htb]

Is the issue easily reproducible ?
Could you try your reproducer on the latest upstream kernel ?