Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3EAB5C433F5 for ; Tue, 16 Nov 2021 13:21:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2551061B29 for ; Tue, 16 Nov 2021 13:21:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236661AbhKPNYB (ORCPT ); Tue, 16 Nov 2021 08:24:01 -0500 Received: from bedivere.hansenpartnership.com ([96.44.175.130]:46646 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230471AbhKPNYA (ORCPT ); Tue, 16 Nov 2021 08:24:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1637068863; bh=Sl6WuLnqTU5TtnSO/QxFeyGJuRtLYuKL8EqqmhmDJXE=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=MPT0whG2bQpz0Y8+0rTOzk/Lt9c8RRm7MpZUKNOWWeP09PrTuZbxrGsGMCDBVFtIB 73aZZDq3UHdFL++Ub3OxRSnL3yZgntpKyZsNEZe8JaDLPYS2yUL+Vf9WsvhhtP0pGY tjqCDNMkJTzaDuHazCXWjzVHrqqtiLkYOTTXFlu0= Received: from localhost (localhost [127.0.0.1]) by bedivere.hansenpartnership.com (Postfix) with ESMTP id 0286C1280119; Tue, 16 Nov 2021 08:21:03 -0500 (EST) Received: from bedivere.hansenpartnership.com ([127.0.0.1]) by localhost (bedivere.hansenpartnership.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dfdi4ZtKv-8E; Tue, 16 Nov 2021 08:21:02 -0500 (EST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=hansenpartnership.com; s=20151216; t=1637068862; bh=Sl6WuLnqTU5TtnSO/QxFeyGJuRtLYuKL8EqqmhmDJXE=; h=Message-ID:Subject:From:To:Date:In-Reply-To:References:From; b=Gh53x5MAbxqanSOf9Z+qToC4xT79AG5yx757N80jyZsGwNIA803bfe57ViasAsXQi 4z92/voDtClOm88EHF5A+G0dQSjdu5NI1LOynI7X+wrinp8pr0XgpF0ALZd0R3BPPB joY1Qno04GjG9pkA6f892MOy/dAQoO90oGkz0myw= Received: from jarvis.int.hansenpartnership.com (unknown [IPv6:2601:5c4:4300:c551::527]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bedivere.hansenpartnership.com (Postfix) with ESMTPSA id 2C450128010E; Tue, 16 Nov 2021 08:20:58 -0500 (EST) Message-ID: Subject: Re: [ELISA Safety Architecture WG] [PATCH v2 0/2] Introduce the pkill_on_warn parameter From: James Bottomley To: Petr Mladek , Alexander Popov Cc: Gabriele Paoloni , Lukas Bulwahn , Robert Krutsch , Linus Torvalds , Jonathan Corbet , Paul McKenney , Andrew Morton , Thomas Gleixner , Peter Zijlstra , Joerg Roedel , Maciej Rozycki , Muchun Song , Viresh Kumar , Robin Murphy , Randy Dunlap , Lu Baolu , Kees Cook , Luis Chamberlain , Wei Liu , John Ogness , Andy Shevchenko , Alexey Kardashevskiy , Christophe Leroy , Jann Horn , Greg Kroah-Hartman , Mark Rutland , Andy Lutomirski , Dave Hansen , Steven Rostedt , Will Deacon , Ard Biesheuvel , Laura Abbott , David S Miller , Borislav Petkov , Arnd Bergmann , Andrew Scull , Marc Zyngier , Jessica Yu , Iurii Zaikin , Rasmus Villemoes , Wang Qing , Mel Gorman , Mauro Carvalho Chehab , Andrew Klychkov , Mathieu Chouquet-Stringer , Daniel Borkmann , Stephen Kitt , Stephen Boyd , Thomas Bogendoerfer , Mike Rapoport , Bjorn Andersson , Kernel Hardening , linux-hardening@vger.kernel.org, "open list:DOCUMENTATION" , linux-arch , Linux Kernel Mailing List , linux-fsdevel , notify@kernel.org, main@lists.elisa.tech, safety-architecture@lists.elisa.tech, devel@lists.elisa.tech, Shuah Khan Date: Tue, 16 Nov 2021 08:20:57 -0500 In-Reply-To: References: <20211027233215.306111-1-alex.popov@linux.com> <77b79f0c-48f2-16dd-1d00-22f3a1b1f5a6@linux.com> <22828e84-b34f-7132-c9e9-bb42baf9247b@redhat.com> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2021-11-16 at 09:41 +0100, Petr Mladek wrote: [...] > If I wanted to implement a super-reliable panic() I would > use some external device that would cause power-reset when > the watched device is not responding. They're called watchdog timers. We have a whole subsystem full of them: drivers/watchdog We used them in old cluster HA systems to guarantee successful recovery of shared state from contaminated cluster members, but I think they'd serve the reliable panic need equally well. Most server class systems today have them built in (on the BMC if they don't have a separate mechanism), they're just not usually activated. James