From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id w+4xCv/fLGco2CgAWB0awg (envelope-from ) for ; Thu, 07 Nov 2024 10:42:55 -0500 Authentication-Results: simark.ca; dkim=pass (2048-bit key; unprotected) header.d=lists.lttng.org header.i=@lists.lttng.org header.a=rsa-sha256 header.s=default header.b=H3bVRMpB; dkim-atps=neutral Received: by simark.ca (Postfix, from userid 112) id F1A551E603; Thu, 7 Nov 2024 10:42:54 -0500 (EST) X-Spam-Checker-Version: SpamAssassin 4.0.0 (2022-12-13) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-3.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=4.0.0 Received: from lists.lttng.org (lists.lttng.org [167.114.26.123]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id E1E6A1E5FA for ; Thu, 7 Nov 2024 10:42:51 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=lists.lttng.org; s=default; t=1730994171; bh=xj/X9s+k5ALNRwPCk6le3HOINroP4nrEUBbsPKD9G4A=; h=Date:Subject:To:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=H3bVRMpBIp1YVmd879xe81qUKyH+7EPlP9Z4/bcPK0HHezX2euY3kLkZEhSm2cmc6 ygL0ZkjuqM4ELB6dzmmmRgvkwvBauWcMkn5w9cfJ3bx4uOinarVv8CtZYRVF1ajQ2C 4WPiRNd8h2aZN2ucZ9G5jdVLxeCz9T3s77qC0hSgvTVNJe2gehsqGrAbmGn60T3c3y imLx0vtHM3c4WDflBJfnS1I9tLp512+GwvQ1k1bWSbHwIPUiIK6CS0pYbSVyE19WY6 Rs1/zgnH44uCRLof9PgQJ/qDooO9sDWu7XEBKHzl3MufHxbUvSPoAsZiPISA+4L1ew QByZ9XVRD3mdA== Received: from lists-lttng01.efficios.com (localhost [IPv6:::1]) by lists.lttng.org (Postfix) with ESMTP id 4XkmYR1xdLz1j9W; Thu, 7 Nov 2024 10:42:51 -0500 (EST) Received: from mail-ej1-x630.google.com (mail-ej1-x630.google.com [IPv6:2a00:1450:4864:20::630]) by lists.lttng.org (Postfix) with ESMTPS id 4XkYw02n7mz1cp9 for ; Thu, 7 Nov 2024 02:43:12 -0500 (EST) Received: by mail-ej1-x630.google.com with SMTP id a640c23a62f3a-a9a0ef5179dso96519166b.1 for ; Wed, 06 Nov 2024 23:43:12 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1730965391; x=1731570191; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=rxh8OOnbyBPMSlQwzeVL/40fkSzeqgHAAp17RLUAWfQ=; b=dGHFTmGuT/4Pd+QsEmx/fBeDL2ezqMrDhsZqkpT++pbd+P6Eck8z0Uc6r/VnwwWOIY /VhI37cfzVenPjVJYR8EraO9yDMqYe5DDg3boFFwFaz6+YMPvYh3+S8EKdyRtMbtsT72 DFMurLEn/XQumWoD53HOwpU0kcjVh4MKy3S6CbN08ZWV3mfUmPMINlflm7vEkQ6qIu10 CC29uTF9ix+yvI6F/lqLFIrSq1g+kPYOI0ZjuHJ/DVpyrZwRiz9Vbb3cURrPDhTVkENh kJKOOF/Sdis7QRkKLh1iqbGNHppcifY6az/A8Hxu77O/Otq0a1r1OnoA6cbMLzYF7dXB xsRA== X-Gm-Message-State: AOJu0YwFKcAH2o/MnjjFJsVt+ry8sGbsqVYx/JjiRijywGvGyh1MznKp aNRhwHMl+VF+QXUrouOvLvU+DrNfO8MFEsM0QgpOBFkGa3fLrWSmP+m1nNwUcaRXj/bM4epcu5M f6hL9aOntGX0jyflvybRp9YUuj/aLVDv0 X-Google-Smtp-Source: AGHT+IHDZchCwPAM6ngS+QHzlgSg4WZAIG/CNnsaMctYem6l7ulIdPCV0AF5d/TMuefQ4Jt4Rb30rW+jU7Eax/suRTw= X-Received: by 2002:a17:907:7da2:b0:a9a:6752:ba80 with SMTP id a640c23a62f3a-a9de5d6e1dcmr4217728766b.5.1730965390639; Wed, 06 Nov 2024 23:43:10 -0800 (PST) MIME-Version: 1.0 Date: Thu, 7 Nov 2024 08:42:59 +0100 Message-ID: Subject: Kernel tracing from inside a Docker container To: lttng-dev@lists.lttng.org Content-Type: text/plain; charset="UTF-8" X-Mailman-Approved-At: Thu, 07 Nov 2024 10:42:49 -0500 X-BeenThere: lttng-dev@lists.lttng.org X-Mailman-Version: 2.1.39 Precedence: list List-Id: LTTng development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Dirk Eibach via lttng-dev Reply-To: Dirk Eibach Errors-To: lttng-dev-bounces@lists.lttng.org Sender: "lttng-dev" Hi, sorry, Outlook is messing up my plaintext mails, so I am switching to my gmail account. > lttng-modules exposes its control ABI through the virtual file /proc/lttng. > > Does you container have access to that file ? The container is running in privileged mode. root@9348eb19e6f4:/# ls -l /proc/lttng -rw------- 1 root root 0 Nov 6 16:05 /proc/lttng > Note that if you give access to that file within the container, then the container > can observe detailed information about kernel internals (including related to > other containers). This is a development-only system, so the security implications are acceptable. I have observed one more thing. When I start the session daemon with the -vvv option I get: root@9348eb19e6f4:/# lttng list --kernel DBG1 - 07:31:23.811796947 [Client management]: Wait for client response (in thread_manage_clients() at client.c:2576) DBG1 - 07:31:23.811867247 [Client management]: Receiving data from client ... (in thread_manage_clients() at client.c:2604) DBG1 - 07:31:23.811945247 [Client management]: Processing client command 'LTTNG_LIST_TRACEPOINTS' (14) (in process_client_msg() at client.c:1016) Error: Failed to load kmod library resources Warning: No kernel tracer available DBG1 - 07:31:23.812076447 [Client management]: Missing llm header, creating one. (in process_client_msg() at client.c:2381) DBG1 - 07:31:23.812085547 [Client management]: Sending response (size: 24, retcode: Kernel tracer not available (33)) (in thread_manage_clients() at client.c:2683) DBG1 - 07:31:23.812156547 [Client management]: Accepting client command ... (in thread_manage_clients() at client.c:2534) Error: Unable to list kernel events: Kernel tracer not available Regards Dirk