From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 13079C4CECD for ; Tue, 17 Sep 2019 07:51:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D5E7421670 for ; Tue, 17 Sep 2019 07:51:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="cmjFVvyB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404516AbfIQHvg (ORCPT ); Tue, 17 Sep 2019 03:51:36 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:34423 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727479AbfIQHvg (ORCPT ); Tue, 17 Sep 2019 03:51:36 -0400 Received: by mail-pl1-f193.google.com with SMTP id d3so1160888plr.1 for ; Tue, 17 Sep 2019 00:51:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=GdV6ui5LZLnW8fFVJkCHLEeDEzLY87U+BmVYVOmxHi0=; b=cmjFVvyBZ27L7F1N/sqThnFHwxhbjLSWiOYMhYapK6G2l9k5eV4rZ+zoeuZHC+79Qz 5k9SeOOedWTrI8+chd90HXxGc87hfPShd+dSpVybZI1g+YtmzWgHVsyWqe7SrkvH3voj n/E9uyVAbMC0F36kyyb65AODfAviRMuUPLiIvfFshs851gDhwt4S6hhzDG11zTQ+AkmJ GIL8dI4Fgo12YuAc/gd1SI2AfbA+tOid2YIod27QIYhfdm8tUYWnNwFgeLEbAyUHw3Sm Y8+vKC2jn/rGSxRNovq0huizTGnKTZGRLmT8ckQtdpXkp0ZJzZPz0M7aqWf4N2oc7/41 AEcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=GdV6ui5LZLnW8fFVJkCHLEeDEzLY87U+BmVYVOmxHi0=; b=pKYpeKdvHcX9+oZEu2PENXkbXoNkqYNaFkO+qwXYDJeAzKuzSZHeyIhf88Vf/Q6C/t +QvaDW/YGYB32zT+HBode/jKrH9a3C1+JcI8jL8S0+kBOEoEee68f6M66i+qFY+h7zAk znN+cbSMIKXmSv/V9iVmos3GtA/1CnzKXe+Aoi6pH39NuMlxFcErn/AZ53RK846KCXwF hDI+AwZwtfr206yXam2g30jOAjyZYDvPpz1s9S3rakMHQq2WeAwMzFWqGBlfq7nH7CXv OeRuDKmUzqNafcSv+OtBoK2W9UhuylEwBMNoTTLONjk5qGP12ZDkmnMrqXAzZm5XdBln 6K4g== X-Gm-Message-State: APjAAAUAZgRRVvds77hILvGgE8gQzdtDZoigPyqbYn6vJXCMDBg6TYxs fXdZOB01FFPHWPtY4Zpo18A= X-Google-Smtp-Source: APXvYqzLvYAN+gNKUQ3BY1oZRmJEV64y8Q783k4xFSVrqm1ok4xmashJ8v9gp1obIubEabAsJY+ihQ== X-Received: by 2002:a17:902:7d8b:: with SMTP id a11mr2293862plm.149.1568706694385; Tue, 17 Sep 2019 00:51:34 -0700 (PDT) Received: from localhost ([110.70.27.73]) by smtp.gmail.com with ESMTPSA id k5sm1521940pfi.142.2019.09.17.00.51.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 Sep 2019 00:51:33 -0700 (PDT) Date: Tue, 17 Sep 2019 16:51:30 +0900 From: Sergey Senozhatsky To: Petr Mladek Cc: Tetsuo Handa , John Ogness , Daniel Vetter , Andrea Parri , Sergey Senozhatsky , Sergey Senozhatsky , Steven Rostedt , Brendan Higgins , Paul Turner , Peter Zijlstra , Thomas Gleixner , Linus Torvalds , Greg Kroah-Hartman , Theodore Ts'o , Prarit Bhargava , LKML Subject: Re: printk meeting at LPC Message-ID: <20190917075130.GA860@jagdpanzerIV> References: <20190807222634.1723-1-john.ogness@linutronix.de> <20190904123531.GA2369@hirez.programming.kicks-ass.net> <20190905130513.4fru6yvjx73pjx7p@pathway.suse.cz> <20190905143118.GP2349@hirez.programming.kicks-ass.net> <20190905121101.60c78422@oasis.local.home> <87k1acz5rx.fsf@linutronix.de> <20190916104624.n3jh363z37ah2kxa@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190916104624.n3jh363z37ah2kxa@pathway.suse.cz> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (09/16/19 12:46), Petr Mladek wrote: > Hmm, it seems that journalctl is able to filer device specific > information, for example, I get: > > $> journalctl _KERNEL_DEVICE=+usb:2-1 > -- Logs begin at Tue 2019-08-13 09:00:03 CEST, end at Mon 2019-09-16 12:32:58 CEST. -- > Aug 13 09:00:04 linux-qszd kernel: usb 2-1: new high-speed USB device number 2 using ehci-pci > > One question is if anyone is using this filtering. Simple grep is > enough. Another question is whether it really needs to get passed > this way. Hmm. If I recall correctly... There was some sort of discussion (and a patch, I believe) a long time ago. If I'm not mistaken, guys at facebook somehow add "machine ID" (e.g. CONFIG_DEFAULT_HOSTNAME?) to kernel messages (via dicts). This has one interesting use case: net consoles print extended headers. So they have monitoring systems, which capture and track net consoles output from many servers, and should one of them warn/oom/etc. they immediately know which one of the machines is "under the weather" (ext_text directly points at the right server). Well, once again, if I recall this correctly. -ss