From patchwork Tue Apr 23 07:21:30 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Xing X-Patchwork-Id: 13639403 Received: from mail-pl1-f179.google.com (mail-pl1-f179.google.com [209.85.214.179]) (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 62F3045BE1 for ; Tue, 23 Apr 2024 07:21:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.179 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713856908; cv=none; b=J2pzBjk9q4M5xB8ZqwJbjiVBklgw2xoSMC9xothYzYEVwMd+VhPSsLybxaFNrwK21dXKIjmka3fawmpJV1/JDxkmTrrebJnP3gnNyxOSPKi3GoSG04xX7LLfcPpyO5WAP4l6JFDFzzfgz+qj9mTnMKA/2qR9pVqq51gWiYDdWqE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713856908; c=relaxed/simple; bh=YBeJMqd38yCDTXGSQCFQ1Z3M0MpdfWLJDuf5kSVsHrE=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=LfrwylIvvRyM/fKgwZ85SnCXUvWdrskzlPs1jcggadaducFUgBqc39Q5CYWDvLxHM2C1mbhskPHZBeztNKob+VgyDFFC29WOqH+MfoJu3q2BoxmwhvUvEmjxlHXo8AgLKwvO/tuMRXuHyC0B8fs0E/Ue8x9U6Fd/cCUHzDB36D8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=A/tSoX4g; arc=none smtp.client-ip=209.85.214.179 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.b="A/tSoX4g" Received: by mail-pl1-f179.google.com with SMTP id d9443c01a7336-1e3c9300c65so45275685ad.0 for ; Tue, 23 Apr 2024 00:21:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1713856905; x=1714461705; darn=lists.linux.dev; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=fWErk60OMZvREVtFAcJcEocSc4JBIDxVWbO7tBYd61Q=; b=A/tSoX4geBs7i9D/mZwVtuyxTPK+OTcpl2y+LkQ7Dg2Z9NTwu9+G8DlAtBbRjKYthO rE+ax0lwc56tc9rMHGgmd7+25CrpqUqiu08044WD+KGy1F6k2SCML4mQwQiyHfF1/rxn /on2THWmvhVGZQ/BkrSBzaVeYVVXOimXiWBWD5sGu0BYKMrGNjoXEkaNfYh0cf+A2e9e W+ED89Kr66LsoWY8WyAbjvbv+7v/zTDB8agZdiZYgot4XSzG6h6Ys9bX/Jbr5GBVA/OG Sht66wn8bpq63Lb6Wd2eieOqvGr/vTllmyDVABFitUCFvgzYgZ9WUVMxO5HtTraQAZEy slUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713856905; x=1714461705; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=fWErk60OMZvREVtFAcJcEocSc4JBIDxVWbO7tBYd61Q=; b=EtNmoCsEDkkvfT1lmiX2nmzXprfPBm8wTRw24tsE+whcE4czNO62ADtYjkKH+5aykj ItAWsv1rWQ1C2eq9K8jTlU2TcM9t+AUMsL3N2nPDHPFSwRxknRVyPCLxftBWeeX7TxMw W+jqcISvv12ckO2KKBVuWZub3mv8ZB2FJ/dwH8BqHVefPzgFuXJHm8ATj9QC+d6MQQdh k+RtH7wsEKrnOwQQoyN4H/EAmFjkS3PS7qDp10A01W8ZrSIBDrUEEYHA6wBuNCiZXaOZ FU1Di9XtKnIGvyyfV0liWDl5tJUmYvImgg+Dq0ih3W6+F2LJa37/grGSs9bd//kN0WCq E1Vw== X-Gm-Message-State: AOJu0YwzzB2PvOSfJDQCzZadwMD3scueEq87DNr9hOCnwprS29W4KYI6 Wp3z0201mR3MpYFOy/YdKOKbhR0s/xv8K8TeQbyBaoZ9sUGpNmMh X-Google-Smtp-Source: AGHT+IFquDDTD40LicZS6AbgVpC1YZJ7/c/75vwmyLpn7BIYRsyKqh69oy58mVxb79glOZMWs7ZkLg== X-Received: by 2002:a17:902:b68b:b0:1e9:6609:37d4 with SMTP id c11-20020a170902b68b00b001e9660937d4mr6536313pls.9.1713856905568; Tue, 23 Apr 2024 00:21:45 -0700 (PDT) Received: from KERNELXING-MB0.tencent.com ([43.132.141.25]) by smtp.gmail.com with ESMTPSA id w19-20020a170902c79300b001e0c956f0dcsm9330114pla.213.2024.04.23.00.21.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Apr 2024 00:21:44 -0700 (PDT) From: Jason Xing To: edumazet@google.com, dsahern@kernel.org, matttbe@kernel.org, martineau@kernel.org, geliang@kernel.org, kuba@kernel.org, pabeni@redhat.com, davem@davemloft.net, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, atenart@kernel.org, horms@kernel.org Cc: mptcp@lists.linux.dev, netdev@vger.kernel.org, linux-trace-kernel@vger.kernel.org, kerneljasonxing@gmail.com, Jason Xing Subject: [PATCH net-next v8 0/7] Implement reset reason mechanism to detect Date: Tue, 23 Apr 2024 15:21:30 +0800 Message-Id: <20240423072137.65168-1-kerneljasonxing@gmail.com> X-Mailer: git-send-email 2.33.0 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Jason Xing In production, there are so many cases about why the RST skb is sent but we don't have a very convenient/fast method to detect the exact underlying reasons. RST is implemented in two kinds: passive kind (like tcp_v4_send_reset()) and active kind (like tcp_send_active_reset()). The former can be traced carefully 1) in TCP, with the help of drop reasons, which is based on Eric's idea[1], 2) in MPTCP, with the help of reset options defined in RFC 8684. The latter is relatively independent, which should be implemented on our own, such as active reset reasons which can not be replace by skb drop reason or something like this. In this series, I focus on the fundamental implement mostly about how the rstreason mechnism works and give the detailed passive part as an example, not including the active reset part. In future, we can go further and refine those NOT_SPECIFIED reasons. Here are some examples when tracing: -0 [002] ..s1. 1830.262425: tcp_send_reset: skbaddr=x skaddr=x src=x dest=x state=x reason=NOT_SPECIFIED -0 [002] ..s1. 1830.262425: tcp_send_reset: skbaddr=x skaddr=x src=x dest=x state=x reason=NO_SOCKET [1] Link: https://lore.kernel.org/all/CANn89iJw8x-LqgsWOeJQQvgVg6DnL5aBRLi10QN2WBdr+X4k=w@mail.gmail.com/ v8 Link: https://lore.kernel.org/all/20240422030109.12891-1-kerneljasonxing@gmail.com/ 1. put sk reset reasons into more natural order (Matt) 2. adjust those helper position (Matt) 3. rename two convert function (Matt) 4. make the kdoc format correct (Simon) v7 Link: https://lore.kernel.org/all/20240417085143.69578-1-kerneljasonxing@gmail.com/ 1. get rid of enum casts which could bring potential issues (Eric) 2. use switch-case method to map between reset reason in MPTCP and sk reset reason (Steven) 3. use switch-case method to map between skb drop reason and sk reset reason v6 1. add back casts, or else they are treated as error. v5 Link: https://lore.kernel.org/all/20240411115630.38420-1-kerneljasonxing@gmail.com/ 1. address format issue (like reverse xmas tree) (Eric, Paolo) 2. remove unnecessary casts. (Eric) 3. introduce a helper used in mptcp active reset. See patch 6. (Paolo) v4 Link: https://lore.kernel.org/all/20240409100934.37725-1-kerneljasonxing@gmail.com/ 1. passing 'enum sk_rst_reason' for readability when tracing (Antoine) v3 Link: https://lore.kernel.org/all/20240404072047.11490-1-kerneljasonxing@gmail.com/ 1. rebase (mptcp part) and address what Mat suggested. v2 Link: https://lore.kernel.org/all/20240403185033.47ebc6a9@kernel.org/ 1. rebase against the latest net-next tree Jason Xing (7): net: introduce rstreason to detect why the RST is sent rstreason: prepare for passive reset rstreason: prepare for active reset tcp: support rstreason for passive reset mptcp: support rstreason for passive reset mptcp: introducing a helper into active reset logic rstreason: make it work in trace world include/net/request_sock.h | 4 +- include/net/rstreason.h | 121 +++++++++++++++++++++++++++++++++++++ include/net/tcp.h | 3 +- include/trace/events/tcp.h | 26 ++++++-- net/dccp/ipv4.c | 10 +-- net/dccp/ipv6.c | 10 +-- net/dccp/minisocks.c | 3 +- net/ipv4/tcp.c | 15 +++-- net/ipv4/tcp_ipv4.c | 17 ++++-- net/ipv4/tcp_minisocks.c | 3 +- net/ipv4/tcp_output.c | 5 +- net/ipv4/tcp_timer.c | 9 ++- net/ipv6/tcp_ipv6.c | 20 +++--- net/mptcp/protocol.c | 2 +- net/mptcp/protocol.h | 39 ++++++++++++ net/mptcp/subflow.c | 27 ++++++--- 16 files changed, 267 insertions(+), 47 deletions(-) create mode 100644 include/net/rstreason.h