From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f175.google.com (mail-pl1-f175.google.com [209.85.214.175]) (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 1D05B204F93 for ; Fri, 10 Jan 2025 11:12:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.175 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736507554; cv=none; b=uCPVDYeuXHSOuEtedqoRJATwO8yT2ydFTrqZLcqwyrCB0TxeJ7GbgoX6uuNX4L0XplhoIe4c0albElVniol0wadmfT6VWxy9trFjzDf3EWdrGzz6k1s36OTLziJAAyuyluz9FYH2s4hGlrRg+pvqAHFcfwB5n0d0TaZj97mQuiY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736507554; c=relaxed/simple; bh=qXSynCY96TYG7wZ7OASI5Muii12uM+aBd0x+fKz2Q64=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fE82IGeDN61HGtSTUi5Nj9IpYJQU/KdKaxt6NAl0Ewh4n36N+UbtF4GXnQa7ywUrNtqOFtGOqQOm2yyhzr6UFlp81VpriavJ/rfd1XlrIKa8Bjiq8UniVTxFd5iGa4hqWQk02S1fzRBJzE/7RBDAM9JuiXCinc5boAxb6RF72K4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=daynix.com; spf=pass smtp.mailfrom=daynix.com; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.b=MwO3UGQ8; arc=none smtp.client-ip=209.85.214.175 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=daynix.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=daynix.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=daynix-com.20230601.gappssmtp.com header.i=@daynix-com.20230601.gappssmtp.com header.b="MwO3UGQ8" Received: by mail-pl1-f175.google.com with SMTP id d9443c01a7336-2161eb94cceso23067145ad.2 for ; Fri, 10 Jan 2025 03:12:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20230601.gappssmtp.com; s=20230601; t=1736507552; x=1737112352; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=fUI/Gf/iNdZ2kON6E6PSrhEkMNvEUQIh/sL8yMhLamQ=; b=MwO3UGQ8TvdlcnS1Er/wPY9ota4qi9gGOgTNt7g7S6YG1L9H3gqX0ExQeXxKJnXL7X XeAWFpsMp3pjyvWra0SCvqOuqk/80Ss1ztp4HN27fDmWYrpuva407XWMh4/xOAEXA3KJ WuOh5DzuQ4gbLE0fUUS7YS/+tghLtkvK+s5eGulTypBG7qqUOlAMyYF9c7Z+TLIAXXwW UE9+ude3fE3mDWHLqpT9hK6iDDqMJCmdSPQ2vfvJ015wBRsVUBZDs2Tw0Jz3m2fwhswE 9BT0HSyyEVIF8eiJ9+cOWEtoHXvBzBFnnCNhJrTMzYH6h9prUzxWAnD2O7WOPlgDTkiH UdzA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1736507552; x=1737112352; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=fUI/Gf/iNdZ2kON6E6PSrhEkMNvEUQIh/sL8yMhLamQ=; b=kJ+QN+WIRqMGXoqSr1/FwCuiN1JzpN3+08gXQgGanAxMFVhJqETRkEnOlx0SXeaG3I eOJv8JYR5303wlDCoIcc/Kdz1Dd1dy+NHubK3tTpJiwOYxMC9nWf40eh9mnWPcTKQht2 3Xgb2lb41evMuSbuJb0E0WpF3QLZ6UeyGlj3PXQZFkjoeWifsqD5DtvEsP+VOBZFsFFj pUlp4fibKm6Z9fEW1BGKJuSfWQOt//8cAR3GfuttZxo7+V+MuZOR6ZEShVrZsMJrpExH faCgawe44rPfw0vbiSDqFKxR0/5PpuBg5+3YDp4h7LS4grcaK3ESP2oQCe+REyGxBxHa MtvQ== X-Forwarded-Encrypted: i=1; AJvYcCUGwxz9tjDisJ/On79VdmSvj0kewkbqZXhuhcUjcyUJ/xsGiG2PofhurEmokuel2kyPQERHYGjh6aMSgPw=@vger.kernel.org X-Gm-Message-State: AOJu0YyCFbq/T4YNPqag7ornnwwe/um7peDJgsCAP2WYuwzZlCN18gTO OEEtAIxK01a0kzz7d4slo1AnDUgK2EdKYwTCDK5Vh4blnuPDoR+Q2plSV6Usdpw= X-Gm-Gg: ASbGncvHgUH1J22fcIWb7ySbsjbvbleeDbqQI65wcTNGQyTfLd2hsb0x5+vViVDpSvp TrX1ZomnjmU/DDmXvZfCbC6wC2T7VxtjSlJiGQiZzRgXzXxelZAKtkw52NK6yd4kkd/vVcT9jgc d5az3YngGMLoz94NCFejlNfH9PT8X4M2f+TP0OvcgE0VpUL18wtejK3hRiqgfqZV1mcFjbSDilM T3RYNSqTBB/vKqh3wOXfWR5c1ZpdctKCOOS0ADk+SNy0juC/s6rEZKoEeMM6EGJ1wY= X-Google-Smtp-Source: AGHT+IFsisJKA6JOrR0eUj5WfV8wXSlwG+ErpDxaHPAWov6uHn2OYu5jltHENp4vvgdoL273AAhZWg== X-Received: by 2002:a05:6a20:244d:b0:1d9:fbc:457c with SMTP id adf61e73a8af0-1e88d0a4770mr18461822637.36.1736507552500; Fri, 10 Jan 2025 03:12:32 -0800 (PST) Received: from [157.82.203.37] ([157.82.203.37]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-72d4056a2cfsm1373935b3a.51.2025.01.10.03.12.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 10 Jan 2025 03:12:32 -0800 (PST) Message-ID: <2e015ee6-8a3b-43fb-b119-e1921139c74b@daynix.com> Date: Fri, 10 Jan 2025 20:12:25 +0900 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 3/3] tun: Set num_buffers for virtio 1.0 To: "Michael S. Tsirkin" , Jason Wang Cc: Jonathan Corbet , Willem de Bruijn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Xuan Zhuo , Shuah Khan , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-kselftest@vger.kernel.org, Yuri Benditovich , Andrew Melnychenko , Stephen Hemminger , gur.stavi@huawei.com, devel@daynix.com References: <20250109-tun-v2-0-388d7d5a287a@daynix.com> <20250109-tun-v2-3-388d7d5a287a@daynix.com> <20250110052246-mutt-send-email-mst@kernel.org> Content-Language: en-US From: Akihiko Odaki In-Reply-To: <20250110052246-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 2025/01/10 19:23, Michael S. Tsirkin wrote: > On Fri, Jan 10, 2025 at 11:27:13AM +0800, Jason Wang wrote: >> On Thu, Jan 9, 2025 at 2:59 PM Akihiko Odaki wrote: >>> >>> The specification says the device MUST set num_buffers to 1 if >>> VIRTIO_NET_F_MRG_RXBUF has not been negotiated. >> >> Have we agreed on how to fix the spec or not? >> >> As I replied in the spec patch, if we just remove this "MUST", it >> looks like we are all fine? >> >> Thanks > > We should replace MUST with SHOULD but it is not all fine, > ignoring SHOULD is a quality of implementation issue. > Should we really replace it? It would mean that a driver conformant with the current specification may not be compatible with a device conformant with the future specification. We are going to fix all implementations known to buggy (QEMU and Linux) anyway so I think it's just fine to leave that part of specification as is.