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=-0.8 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 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 BB863ECE58C for ; Fri, 11 Oct 2019 14:04:12 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 14C4B214E0 for ; Fri, 11 Oct 2019 14:04:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ZMU//ZSO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 14C4B214E0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-17010-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 32131 invoked by uid 550); 11 Oct 2019 14:04:03 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 32094 invoked from network); 11 Oct 2019 14:04:03 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=qLKPKRGYsWe2LV9feXXSxEVMb4o9FMaaiM9B0N1Xmkg=; b=ZMU//ZSO/ORdlfd+RmY9p6kVfciAI9jtv2PKCNwsuCYK/SXTxr3/qm7xCjI5oXl9RS Gv+TBdGCNnY/LWloGh9h6txsenW3VTUMI5QrYnAS1dhR+sC4Sg+ObOz9pY78fr8ZQkIP AX4jEiZ1++VJNYTdZrYy045YGmSn2uiowR0VkLVhwDDJVplCsQeN4qORGZpVmXAJwh5t udhKZMcwYbZkSjGIAAsPggg3ZJzB7cv/SiA7AlNR2vepPgu5ctumDeiXE7PmYW1TYgjb YxkXjdsxbtSVRLqEq8GWn2f1MlZbPtK97pd8PJMafNcWvAT22O9eY2rp/Qw/h2Tzu0pK 6KEA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=qLKPKRGYsWe2LV9feXXSxEVMb4o9FMaaiM9B0N1Xmkg=; b=cIL6R96BZAyCblMP0IeZRPR7+a5i7RvanHmsyIOMbfrARHymELmsFQDkuT04TTwcz1 lwax1dXR6UNrXRQ6i6yghyWsrcpTPmeo3q0+4MGT89yqkMJnDESg9XKG/QQ5X2+eZPQ7 Y0tO/Yb2ETs6ZfRZzLrN1zZ67nDG3kgUpcuyAemclD8LYFLvbRKc+fZsZogqi+sO1z8w TweWaZXVuxmD4w2CKQPWazqKBB4o8E8Q4xQL6DugOjQ3almuqQ7bxP2jPuGseI2Q7//u N+tGtGAwoWqa1tyuflfb0qIdND+fMHweOhtfU+b4YvQWmFQQXI/WaDsHxpJAvUJKYvHn GZ6w== X-Gm-Message-State: APjAAAUJ9ARI0Mrnlo2Vi8yVna0rR8cbcjih/Uf/Hoq0HvtQNcZHrpgR o2Vha1y8JXbuh3VEHQZo4p/NuCudr16R+wgCMdo= X-Google-Smtp-Source: APXvYqy7r1uh0ASgmB4F0b6aSaWniIcpiEYPxQ6n979GmK5Aaxvjo8JAffurrAOCfBJye9jb/HY9ga6gM43upT2m/l0= X-Received: by 2002:aca:dcd6:: with SMTP id t205mr12439954oig.128.1570802630804; Fri, 11 Oct 2019 07:03:50 -0700 (PDT) MIME-Version: 1.0 References: <201909301645.5FA44A4@keescook> <201910031417.2AEEE7B@keescook> <201910100950.5179A62E2@keescook> <201910101106.9ACB5DB@keescook> In-Reply-To: <201910101106.9ACB5DB@keescook> From: Muni Sekhar Date: Fri, 11 Oct 2019 19:33:38 +0530 Message-ID: Subject: Re: How to get the crash dump if system hangs? To: Kees Cook Cc: kernel-hardening@lists.openwall.com Content-Type: text/plain; charset="UTF-8" On Fri, Oct 11, 2019 at 12:01 AM Kees Cook wrote: > > On Thu, Oct 10, 2019 at 10:45:21PM +0530, Muni Sekhar wrote: > > I'm using Ubuntu distro, ran "reboot" command but after reboot > > console-ramoops-0 is not present in /sys/fs/pstore > > Hmpf. Well, then, I guess your boot firmware is pretty aggressive about > wiping RAM across boots. :( > > There was a patch set to store to disk, but I haven't seen a recent > version of it, if you want to go that route[1]. > > -Kees > > [1] https://lore.kernel.org/lkml/1551922630-27548-1-git-send-email-liaoweixiong@allwinnertech.com/ Thanks I will check it out. While loading ramoops I see "persistent_ram: uncorrectable error in header", is this harmful? [ 270.864969] ramoops: using module parameters [ 270.866651] persistent_ram: uncorrectable error in header [ 270.867252] persistent_ram: uncorrectable error in header [ 270.867728] persistent_ram: uncorrectable error in header [ 270.868067] persistent_ram: uncorrectable error in header [ 270.868492] persistent_ram: uncorrectable error in header [ 270.868839] persistent_ram: uncorrectable error in header [ 270.869209] persistent_ram: uncorrectable error in header [ 270.869681] persistent_ram: uncorrectable error in header [ 270.870026] persistent_ram: uncorrectable error in header [ 270.870430] persistent_ram: uncorrectable error in header [ 270.870774] persistent_ram: uncorrectable error in header [ 270.871110] persistent_ram: uncorrectable error in header [ 270.871687] persistent_ram: uncorrectable error in header [ 270.872055] persistent_ram: uncorrectable error in header [ 270.872567] persistent_ram: uncorrectable error in header [ 270.872910] persistent_ram: uncorrectable error in header [ 270.873243] persistent_ram: uncorrectable error in header [ 270.873592] persistent_ram: uncorrectable error in header [ 270.873932] persistent_ram: uncorrectable error in header [ 270.874267] persistent_ram: uncorrectable error in header [ 270.874614] persistent_ram: uncorrectable error in header [ 270.874958] persistent_ram: uncorrectable error in header [ 270.875300] persistent_ram: uncorrectable error in header [ 270.875686] persistent_ram: uncorrectable error in header [ 270.876028] persistent_ram: uncorrectable error in header [ 270.876462] persistent_ram: uncorrectable error in header [ 270.876808] persistent_ram: uncorrectable error in header [ 270.877144] persistent_ram: uncorrectable error in header [ 270.877519] persistent_ram: uncorrectable error in header [ 270.877860] persistent_ram: uncorrectable error in header [ 270.878199] persistent_ram: uncorrectable error in header [ 270.878565] persistent_ram: uncorrectable error in header [ 270.878916] persistent_ram: uncorrectable error in header [ 270.881129] console [pstore-1] enabled [ 270.884817] pstore: Registered ramoops as persistent store backend [ 270.885232] ramoops: attached 0x100000@0x3ff00000, ecc: 16/0 > > -- > Kees Cook -- Thanks, Sekhar