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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 E0412C3A5A9 for ; Mon, 4 May 2020 19:12:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD335206C0 for ; Mon, 4 May 2020 19:12:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Si7dlb0A" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726761AbgEDTMP (ORCPT ); Mon, 4 May 2020 15:12:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725956AbgEDTMO (ORCPT ); Mon, 4 May 2020 15:12:14 -0400 Received: from mail-pf1-x444.google.com (mail-pf1-x444.google.com [IPv6:2607:f8b0:4864:20::444]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 426EAC061A0F for ; Mon, 4 May 2020 12:12:14 -0700 (PDT) Received: by mail-pf1-x444.google.com with SMTP id r14so6024900pfg.2 for ; Mon, 04 May 2020 12:12:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=DRRJVsf51l5t9Dm4TlhSU/EZbXOvcOE4YxM3FowxRF0=; b=Si7dlb0AnRhxMKmPOWWmPJJFBiUT4hTbUEZ13DYzEVOo2Il6yfzy/8I4eF85hIu4Kg JTsIF/Gth/JFANckJbrIiWa1vqiV+Kn8c9EHteuh/ReoJW0U5GlArClgOw2sVllSjRef 3fe1eu6sfxWOOEXu+wxVB1GNh8zSo/xAskcUQ= 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; bh=DRRJVsf51l5t9Dm4TlhSU/EZbXOvcOE4YxM3FowxRF0=; b=nsVYsSuLbX64Pt3hnan38sVfSVPg4fVMjpbMEz+Vavz67emtpn4eKKEuIwrkB7LDpd fy259OEsDtfkenYZJfB5nvMQ2seyPGrGVoIRmEkUa7l9bLWGjenL/4tUPH16MNRlOfMS MyuXxx8TnbWqT4y6vEh8PpEPnnCuikEPjIjZQ5pCL3DM2eoIDHJq11Oe2340I3E2uFxX q+jtO+PMH00ZuwAnLv1gtVAcWWBrCq74RVcIdvcU+w0hKgfp32QI8nCcmpIJy519IC2M lgCQ3qJDi+6uJ0N3f0ZAU9OzMBoSqZMEIAQP0WH/SUC6qob8XzM1+iduWWK2mIT463vn Jsew== X-Gm-Message-State: AGi0PuZJd+m+Q/COi06NRMi8IZuUuZ+m32Udtc4rEuk4Dx5qhDvAKrWg QX4yx70B7sdu70i3ET+c5lPsXhLssS8= X-Google-Smtp-Source: APiQypK9UGDyEzyZDsYFS7KmpnuRRHd1CKSUuVF2CV0RkZbNly3BomdV876VP1jJ+iRSqqtxTefo9g== X-Received: by 2002:a63:7e1b:: with SMTP id z27mr403821pgc.19.1588619533882; Mon, 04 May 2020 12:12:13 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id s4sm1730400pgv.78.2020.05.04.12.12.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 May 2020 12:12:13 -0700 (PDT) Date: Mon, 4 May 2020 12:12:12 -0700 From: Kees Cook To: Pavel Tatashin Cc: James Morris , Sasha Levin , LKML , Petr Mladek , Sergey Senozhatsky , Steven Rostedt , anton@enomsg.org, ccross@android.com, Tony Luck , robh+dt@kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH v1 0/3] allow ramoops to collect all kmesg_dump events Message-ID: <202005041211.040A1C65C8@keescook> References: <20200502143555.543636-1-pasha.tatashin@soleen.com> <202005041112.F3C8117F67@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 04, 2020 at 02:47:45PM -0400, Pavel Tatashin wrote: > > > # reboot -f > > > > > > After VM is back: > > > > > > # mount -t pstore pstore /mnt > > > # head /mnt/dmesg-ramoops-0 > > > Restart#1 Part1 > > > > Is there a reason that using ramoops.console_size isn't sufficient for > > this? > > Unfortunately, the console option is not working for us (Microsoft), > we have an embedded device with a serial console, and the baud rate > reduces the reboot performance, so we must keep the console quiet. We > also want to be able collect full shutdown logs from the field that > are collected during kexec based updates. I meant collecting console via pstore (i.e. /mnt/console-ramoops-0). Are you saying that's still too large for your situation? -- Kees Cook