From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=74.125.82.176 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794242623; b=NuqPHONVtZeX8SksXS8gIPrkv+OZyJ5kPOi2vbH9Fipx8DiX16W6SVvkOwNBsUcy0Q6A 8Z+NJMg+29EP0Gj+l66gLsZmehmpp2vQcbKuynujT5bxQxUV638dESYPzlj2E7MfSVH3K epClugETHaqApftm93LJzsrXG8p4KKLh/wxZH7GiSMlCu8pWfwnX0i5O4KBlW0huWkmU+ KIBdLlJxn09mLrRkUEqM9PM50GkkkWEu/kFUEznLI/J2P6kvV14mH8BIflwYcEFtOpj7C fUgg8ZFycQyoX+2pGZdjJIUeEGssDhif5Mw6Ayo1zrUZkwLGba9pEbYH1aYHCAR3Ezw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794242623; h=DMARC-Filter:Received:DKIM-Signature:X-Google-DKIM-Signature: X-Forwarded-Encrypted:X-Gm-Message-State:X-Gm-Gg:X-Received:Received: Content-Type:Mime-Version:Subject:From:In-Reply-To:Date:Cc: Content-Transfer-Encoding:Message-Id:References:To:X-Mailer; bh=cTcx+iYQEwQqlDWtvuitNRUigxF9/D90op7v+uRHdIo=; b=0qbwlV+2OjI/46Kiasm7KB423850xIpnsJDa3lnHNSei7GsyKoUN/MyQdReW6dcbk4z0 40VwjtyNFYtb74E66aQwSXRiOUKcl68FP7RuSU+cav8Z2WpkJ9hjEPgKhp4DEuwDvil+A pKCutQPXfg1y5bw+mBSCE4CCX6MC4LFRKc1cDxGoR7a/jhKxTZ+myxwG/AW2wELOI8XrC LRKL+Iaw9uB/WYAEMXs+T+P7IjZusTyprSVIxlC+gcXdyPzvIKOoYKQCT/KYZy6gW1P3h c9ajGdtos1BoQGTmQ2wuMlfTK5iLQA9uOzo+52+RqZAzpGT6AJ94G9IvxL+2IreeWtA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b="K/BCf1Cc"; arc=none smtp.remote-ip=74.125.82.176 Received: from mail-dy1-f176.google.com (mail-dy1-f176.google.com [74.125.82.176]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1C0FA606A330 for ; Mon, 9 Nov 2026 16:43:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 1C0FA606A330 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20260707 header.b=K/BCf1Cc Received: by mail-dy1-f176.google.com with SMTP id 5a478bee46e88-36eb1cb7aabso1682536eec.0 for ; Mon, 09 Nov 2026 08:43:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20260707; t=1794242622; x=1794847422; darn=vger.kernel.org; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:content-type:from:to:cc :subject:date:message-id:reply-to:content-type; bh=cTcx+iYQEwQqlDWtvuitNRUigxF9/D90op7v+uRHdIo=; b=K/BCf1CcnsbXSn9afua9y6dCw1fhSD50tx15jtTyJSp6Mk6ALw+eZxpNTvhTCPVolO 4RrA2wNZS3czpBVR6OqVHo0Iyx2vrY/tlhd1/kMAIGH6GEZ0r4NG4CU7sFNUEV6tPyjK ADdkObIkw56597yAY2xrIgg2QNQz6i8TKD4jPnGF6rCxhHTRHkgazvdPnyd7WFylvxaT gLAiq4bOZguDFEc7i4+5N6hm3VmXkv+BoN1iaWv6PN2swkzOhaOo92J7BoEMGe1zZTrm 49n7kc6/a5Cp2FSzJxx8kIoPngYm/UydiZadvmY/BHHDNT5kVHgEeTc7Co4b2xG8vPKR lctA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1794242622; x=1794847422; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:content-type:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=cTcx+iYQEwQqlDWtvuitNRUigxF9/D90op7v+uRHdIo=; b=VoKGxqIM2anp1PPkjcC4VVBQTB7J4aSlQlXnDR5rE1p1BjlLCj1wL7oVien4+SIUZK MDCGlUeutjmhmmoSsKitNgV4ijw05rRFqY8ML34QXZSCbSZqcrJXbVrYp1LfCM9N3mOW zbh6CobZ2Zx7sbo260w53SuYRpQD4XnPh21r4pEP+RmWFM61Sk3gDIIdnpQaw0PswqOy lWF2uz5nv/ybdhu+ffOYQsygXh21OwTqSCO92px82kcWAl1QAeo5qEI4GwrW7tIR1Bne 3jZ8H5r6hpTdg8r1bSouCzIVVPCt6iDaywLzfll75wlm/+eWwyf+S3UFac643Ckg6MMt RPgw== X-Forwarded-Encrypted: i=1; AL+hErGYgvV+5JcG0rttKxUUihSd5mMcOy5NucLJUtyGPhD4Jdc5Cls86If12w9NICgSanvkjQ2zJEmV8Ehh7o8=@vger.kernel.org X-Gm-Message-State: APuU4Z8TZB6W7YFsTt19Y7Hn22u5nQQciVnYvAQ2HBmkOF+wtfEkdG5E 3niErizvgztSupgfazvH1v8XTmReSNNox5PImVYiq9ANxuyHM6ND1zRx X-Gm-Gg: AYBFou2tIsz4BajEhcPI6RtgI6r/5KuNrYQAJuZ0QZ6I7aXB1XTAcmB/HDzKjqFIR2x /9UYhmvfNvb8JLq13pQSMEYOAdMG3QH2AIni8VnGJuEqtFQo+SbAgmtLfpSpWWl47UyrfjR/8Ln IuWFXLcPZl0zRNeSfPoQqvbn5QcwzGQVhsCOW9L3ENBNiEUW+gInp3kv+rOrpXGkCUK+d/BVYcm e+6K1eg0JB4jV7EdizwGynSmQAEkdFwWsMV8aSkHBfh1dRcarPe78CyfBYE5XG9oLKmWS289NYR R+E2/u1fWr1tMUOIW+gpeC138iiQ1JcrsdNjXzLRfrKHILn1RDFFD9hML5J4+smgDTegpoRKUZ5 /0k+084Q6qagzwxTU5zRmfNfmtm9PICAABCKCt+FGeAhy7pcxtxNVG8FJCpixZcMmFYwfe2Sctl yXKeccyTyKWB76aol7+LIzLE/kQMJUXNMvp0+qeayV5XJReuOe8Vaj7AU/IRAVVBriG+/cnD1eD ErqYvjPl85TociAL6E6N57mjiDb5O/SifdWYPHvHah3cIgY3Yw/TekR6ocLuaRAHfjQejKneqBE qXcrIsRT8f8mp/Q+qIWwwMiBIuCWmaviNTpbDo+IgjKL7m6lO3NDvLUazPZYqvsVRnFCN7Neg0p hdS3kqUMAcdxA X-Received: by 2002:a05:7301:180b:b0:36a:1732:1e7 with SMTP id 5a478bee46e88-37255e4c0fcmr8052837eec.31.1794242622101; Mon, 09 Nov 2026 08:43:42 -0800 (PST) Received: from smtpclient.apple (v133-18-180-162.vir.kagoya.net. [133.18.180.162]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-372665db733sm12958545eec.23.2026.11.09.08.43.37 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Nov 2026 08:43:41 -0800 (PST) Content-Type: text/plain; charset=us-ascii X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3901.100.1.1.12\)) Subject: Re: [PATCH net-next v2 4/4] selftests/net: packetdrill: add TCP MTU probing test From: Esko Mobius In-Reply-To: Date: Tue, 10 Nov 2026 00:43:25 +0800 Cc: davem@davemloft.net, pabeni@redhat.com, horms@kernel.org, kuba@kernel.org, kuniyu@google.com, shuah@kernel.org, edumazet@kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, panweiping3@gmail.com, netdev@vger.kernel.org Content-Transfer-Encoding: 7bit Message-Id: <93CEDEF5-5204-42D1-AF92-C63D64546D31@gmail.com> References: <20261108-mtu-probing-series-v2-0-355d6490c3db@gmail.com> <20261108-mtu-probing-series-v2-4-355d6490c3db@gmail.com> To: Neal Cardwell X-Mailer: Apple Mail (2.3901.100.1.1.12) > AFAICT if we drop the tcp_timestamps=0 line here (so our SYN offers > timestamps and the scripted SYN-ACK declines them), the script should > pass unchanged with patch 1/4, and fail without it (2072-byte rather > than 2048-byte TSO packets, i.e. 2 x 1036 bytes). So I'd suggest > dropping that tcp_timestamps=0 line. That way this test also covers > the active-side part of patch 1/4. Thanks, Neal. I removed the timestamp override and updated the commit message. The revised test passed with patch 1 in all three IP modes on x86_64 KVM. On the same net-next base without patch 1, all three failed on the first data packet. Packetdrill expected 2048 bytes of TCP payload and received 2072, as you predicted. v3 has this change. Thanks, Yongjian