From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f174.google.com (mail-pl1-f174.google.com [209.85.214.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5BB2729BDBB for ; Mon, 23 Mar 2026 23:14:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774307687; cv=none; b=BsIPsNiEqvHLNfBEBcCsq1SAcTQJrn6UYIe5IwLFLhOHSSypFGab8qfsduvpVuLP7GxziDkwBynXUWi2+K367lUHiHBDGkenIh0wRStm1QK6RHHOZwmXSKkT5iqdEqB42+o7Y6aUbcYe7+xD9LP85ESbGZslA/NegBX0Jk8dii8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774307687; c=relaxed/simple; bh=psUtjzbVDqbRSHLGIFO49jP1GHoaJM92TMwHfn0BiPY=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=gveLlwpHe5l6hp1y7YYK7xPdJvTA9lEy7D6JHxZJHBUAmLYT5mFx3IBV9fSvuGS5FABynJu3QALLmQJwxoZXIOFWbaBpr/s0wiaNwVXZOWuaZ9Lb3mCPBpiXkNb0udkK6SJBdlgNDw8tCRtZS0O0S0W5e3UrFJIvFyLDUGD+CUY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=networkplumber.org; spf=pass smtp.mailfrom=networkplumber.org; dkim=pass (2048-bit key) header.d=networkplumber-org.20230601.gappssmtp.com header.i=@networkplumber-org.20230601.gappssmtp.com header.b=zz6c8Y8z; arc=none smtp.client-ip=209.85.214.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=networkplumber.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=networkplumber.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=networkplumber-org.20230601.gappssmtp.com header.i=@networkplumber-org.20230601.gappssmtp.com header.b="zz6c8Y8z" Received: by mail-pl1-f174.google.com with SMTP id d9443c01a7336-2ab39b111b9so14795005ad.1 for ; Mon, 23 Mar 2026 16:14:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1774307686; x=1774912486; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=oMg3lNbBP8Ca7xUJowkSGVPVJMZjC1tfGW4sMdbdTf0=; b=zz6c8Y8zwUQ4dHdrg48xxeerVdMNyfpXfX/4nwOeKcQJIS9RIg7oQVDMnzsmrpenMP XuOLAB0fkSDa6aVEnsvhG01qrWLQPJbRJhLOvYq0S2TlRwvC6dyxwu08GctqDJChWPAs 8f0mB1kKYCOArxw2TABKOiezibxjpOUu5qbO8++ac5udejt5ia9npQIXQVY/hkVUL3OX XFOqNelGLyEKzmn4yUYq9fzjUuycRTES80DN6qko6/MP7faJf6LJJ3huU9q1ICpYykLv nt/ZcJFJ4F/lc8xdhS/Ja1hJroxvGudYym6yW7X4CrSGUYZAgnZxnl3NlDaLjwGb24mg D9ZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774307686; x=1774912486; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=oMg3lNbBP8Ca7xUJowkSGVPVJMZjC1tfGW4sMdbdTf0=; b=kNqnCY6H0EXGeJmldmOShgFJfvNUvKaFlpRlo7BXy/Jhd1cQ1RIqdQ1cTSgOnzjqpL nQzinmI/VQIRMH7bQOQ//5l4nvIWX92qWalyLknO2OKLQ5luGplfQOzQUJ0zqGWtsaJq yS4qd2GFFHfMNSTBmjB5Zxej8rDzoAKKSd5gposBQjEJFZmdNBytosGRVKOJLCxCFyX/ SuP7/4mJDpj/hVKFv8b3Xb20I7J3jVnRD7lttMb/U8yHId0jSRslFgnVWeq3LMk3KT22 s5aIxp6wvioDLWrwFPDViiXVgNn2jLb3WUOo4+Cc83/NFAgKLLYW1CffG4aaDDZbzp2m ZUyw== X-Forwarded-Encrypted: i=1; AJvYcCVu3Z2ZNiiW1dgoMc+SNTWgt6coOFJk6ngNaky6YXXiuXZe7jI99wtfwwLzyXPMsE0Y9Wgcjyg=@vger.kernel.org X-Gm-Message-State: AOJu0YwVnJaUAsPN5wyxjoQV2rPm5N5ztzfTJ7Urnll2xrA/0M/ZirEI PMAUer4NYpOOwLzLTQOuh9SHfF5BYnvEKLyLtbsZ427tJ1gJoRZcFc4rfRONfnTcxO0kfa1vN39 sqD8w7cM= X-Gm-Gg: ATEYQzxjc7SEmoOYFrFWWFeqiCFFawSIrz+rIBu0PRf2m3gfNA5GFfLfLI1J5OVeV8K cRxO99quk2tSUeM2CCEM92pHTB3eeZk29rODWkUyJqHBVR9Xh8MmgeuzlbbhQWguNqXSR5LeOpt auj/D+hnEgEKVeHt8A2CVQPNNMnQxJB1mX/8AoKUv2cYKYNtfDWg5HJM24Eo/4V94dVKUhXm7SW j7jKm+zGODdMNKR3KWL2CDw6D2NhBmAExpbqYQP3RNNPrAdTupVls2wu/YR+yZZDYWH8MnsyNGq c5mqNeCCCxilYWDlYappBSc2W09FVO/D2Xr2Ui1DtM8oFpHKHzwWBK+UayiYaMFGKu007p2DJMz JWOIpGiuPuzNwJXYkifUF4skOdJ1YaDXW0BXBk7nnFrA5c/JFdkx+Wt81pvswqLXXDB50D6ZxtC oac/gvQ6HSJtZHaQ1J3fClXeYxQ2igDU1Uf8U= X-Received: by 2002:a17:902:d4d2:b0:2b0:7a27:bb2b with SMTP id d9443c01a7336-2b0827a9076mr134541315ad.34.1774307685654; Mon, 23 Mar 2026 16:14:45 -0700 (PDT) Received: from phoenix.local ([104.202.29.139]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2b083516aa6sm165708025ad.9.2026.03.23.16.14.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Mar 2026 16:14:45 -0700 (PDT) Date: Mon, 23 Mar 2026 16:14:31 -0700 From: Stephen Hemminger To: William Liu Cc: Jamal Hadi Salim , netdev@vger.kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, horms@kernel.org, jiri@resnulli.us, victor@mojatatu.com, xmei5@asu.edu, pctammela@mojatatu.com, savy@syst3mfailure.io, kuniyu@google.com, toke@toke.dk, willemdebruijnkernel@gmail.com Subject: Re: [PATCH net v2 5/6] net/sched: fix packet loop on netem when duplicate is on Message-ID: <20260323161431.4d6915eb@phoenix.local> In-Reply-To: References: <20260316211052.332383-1-jhs@mojatatu.com> <20260316211052.332383-6-jhs@mojatatu.com> <20260316175705.2ef5004e@stephen-xps.local> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 19 Mar 2026 01:25:59 +0000 William Liu wrote: > > > Would prefer that if ttl is exhausted packet was dropped. > > > Rather than silently not duplicating. > > I think silently not duplicating better matches the semantics of preventing duplication of duplicates, which is the goal of the fix. Ok, I was more considering mirred -> netem case. Whether that is a reasonable configuration is debatable. For the case of duplicate of duplicate, yes that should not happen.