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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,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 B4CA0C433DB for ; Mon, 22 Mar 2021 10:09:17 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 326E361969 for ; Mon, 22 Mar 2021 10:09:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 326E361969 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 031466B009E; Mon, 22 Mar 2021 05:50:26 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0077D6B00A0; Mon, 22 Mar 2021 05:50:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D9CCA6B00A1; Mon, 22 Mar 2021 05:50:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0102.hostedemail.com [216.40.44.102]) by kanga.kvack.org (Postfix) with ESMTP id BAA836B009E for ; Mon, 22 Mar 2021 05:50:25 -0400 (EDT) Received: from smtpin31.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2FAAF18027F8D for ; Mon, 22 Mar 2021 10:09:16 +0000 (UTC) X-FDA: 77947087512.31.2E2F012 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf25.hostedemail.com (Postfix) with ESMTP id B05006000108 for ; Mon, 22 Mar 2021 10:09:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616407754; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=14EzcGArmqO6h8+AWRrdUIs8uwzxBO4aWZ95muOr39M=; b=MFbNaVwGdnWNgMN+W3jaaKCMmf8CwSDDPuiNNqyjhTxxE3/qO4ibbKmFUAc1LFT2EFkArg O+Q73unje/dhLkQGreyqEWKyDD1mbi8nmVTRGKT8BqDvSEJJb1icmvuNI6uKnEPjlyisZ2 QMFT7Cn2SmXV8FNDctL6l/TZDe+0jD0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-44-BapOTyt9N5CbcTZ7LUSx4Q-1; Mon, 22 Mar 2021 06:09:12 -0400 X-MC-Unique: BapOTyt9N5CbcTZ7LUSx4Q-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 54D2983DD21; Mon, 22 Mar 2021 10:09:07 +0000 (UTC) Received: from [10.36.115.54] (ovpn-115-54.ams2.redhat.com [10.36.115.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 9C4F260BE5; Mon, 22 Mar 2021 10:08:48 +0000 (UTC) Subject: Re: [PATCH RFC 0/3] drivers/char: remove /dev/kmem for good To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Alexander A. Klimov" , Alexander Viro , Alexandre Belloni , Andrew Lunn , Andrew Morton , Andrey Zhizhikin , Arnd Bergmann , Benjamin Herrenschmidt , Brian Cain , Christian Borntraeger , Christophe Leroy , Chris Zankel , Corentin Labbe , "David S. Miller" , "Eric W. Biederman" , Geert Uytterhoeven , Gerald Schaefer , Greentime Hu , Greg Kroah-Hartman , Gregory Clement , Heiko Carstens , Helge Deller , Hillf Danton , huang ying , Ingo Molnar , Ivan Kokshaysky , "James E.J. Bottomley" , Jiaxun Yang , Jonas Bonn , Jonathan Corbet , Kairui Song , Krzysztof Kozlowski , Kuninori Morimoto , Linus Torvalds , Linux API , Liviu Dudau , Lorenzo Pieralisi , Luc Van Oostenryck , Luis Chamberlain , Matthew Wilcox , Matt Turner , Max Filippov , Michael Ellerman , Michal Hocko , Mike Rapoport , Mikulas Patocka , Minchan Kim , Niklas Schnelle , Oleksiy Avramchenko , Palmer Dabbelt , Paul Mackerras , "Pavel Machek (CIP)" , Pavel Machek , "Peter Zijlstra (Intel)" , Pierre Morel , Randy Dunlap , Richard Henderson , Rich Felker , Robert Richter , Rob Herring , Russell King , Sam Ravnborg , Sebastian Andrzej Siewior , Sebastian Hesselbarth , Stafford Horne , Stefan Kristiansson , Sudeep Holla , Theodore Dubois , Thomas Bogendoerfer , Thomas Gleixner , Vasily Gorbik , Viresh Kumar , William Cohen , Xiaoming Ni , Yoshinori Sato References: <20210319143452.25948-1-david@redhat.com> <20210319141018.5ee1a5ac@gandalf.local.home> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: Date: Mon, 22 Mar 2021 11:08:47 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20210319141018.5ee1a5ac@gandalf.local.home> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: B05006000108 X-Stat-Signature: 73a7x3xqrs8de34zgjqwsj7e1gzd4u85 Received-SPF: none (redhat.com>: No applicable sender policy available) receiver=imf25; identity=mailfrom; envelope-from=""; helo=us-smtp-delivery-124.mimecast.com; client-ip=170.10.133.124 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616407755-924380 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 19.03.21 19:10, Steven Rostedt wrote: > On Fri, 19 Mar 2021 15:34:49 +0100 > David Hildenbrand wrote: > >> Let's start a discussion if /dev/kmem is worth keeping around and >> fixing/maintaining or if we should just remove it now for good. > > The last time I used /dev/kmem was in 2003. While in Germany, my home > firewall (in the US) got rooted. I could ssh into the box but had no way to > shut it down because the rootkit took over all those commands (luckily it > still allowed me to become root). I finally killed the box with: > > # ls -lR / > /dev/kmem > > ;-) Wonder if "echo c > /proc/sysrq-trigger" already existed and would have worked back then. :) -- Thanks, David / dhildenb