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=-5.8 required=3.0 tests=BAYES_00,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 6B49AC4320E for ; Fri, 6 Aug 2021 06:28:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A193611C5 for ; Fri, 6 Aug 2021 06:28:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241983AbhHFG3B (ORCPT ); Fri, 6 Aug 2021 02:29:01 -0400 Received: from new1-smtp.messagingengine.com ([66.111.4.221]:45143 "EHLO new1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229581AbhHFG3A (ORCPT ); Fri, 6 Aug 2021 02:29:00 -0400 Received: from compute5.internal (compute5.nyi.internal [10.202.2.45]) by mailnew.nyi.internal (Postfix) with ESMTP id 7F7A6580B73; Fri, 6 Aug 2021 02:28:44 -0400 (EDT) Received: from mailfrontend1 ([10.202.2.162]) by compute5.internal (MEProxy); Fri, 06 Aug 2021 02:28:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kroah.com; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm1; bh=eWVlY49TeLxeXcwOp6RoCArUbxW pC9ZgtJzQ3VYEJu8=; b=VKvPK9QLfcxaD53WyA4abxkXFYGC2lbJ9Sp3NVV75jH HxY4YZp8zdAnhfYBgyGO8Hc7CHqrLoFyeb7U9KS9midrtgXn6ubeddqJfNCsIcUD QgOMGWOyK0mfY55wYMl59jb4CTnWqKI4pJ6bDiSd3te8lOG1vDK0bP7Z7N+A5hqQ QzxcH7bLizVOJA8G84krha94crfM8IeFvsEoe0tIikxupEPnvteHMMtG5G8ci2bp 59n8sDDaBxFISNAl13yjRUvc1ljYboeux1zjI7pzs2bRPXgq4ckecz0DzZUJPUgv ZleVORvq5/110wAzHVh9+hHfrsZDUxPBTz6Hrdho53Q== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm3; bh=eWVlY4 9TeLxeXcwOp6RoCArUbxWpC9ZgtJzQ3VYEJu8=; b=ANlIL+aE+oSIEyyaz/PfzR 4b8jxfX6peebx5ePhv/6TZpECcibgNjHncllgtanibeCYfJj1LUGRwmNhhqyXkJ1 KTOdRADhzdvWfOGMdFHWMvn0WIqddg4gSzIZG+H45V6gKZiGjgBnsjbPJGqANC0q kcxj0Kkdhe6Ui2Q/m14fQ5XwXFZZV9Yv4ilu+tHcam8G1SSJiN2ogq+Zjse3MdYA Q1oJTEbQnMgjeK6A8y87MQKYPy4jWOSUrhclgzxfIiDDE/lHzwZSAqkpURShXOgK p4gS7SUdpa0ueFE8YuM5uHEOdfyrWx13rJJGo8eZzWIhUjWPnkfzUAhN4uAVEFIA == X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvtddrjedtgddutdefucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepfffhvffukfhfgggtuggjsehttdertddttddvnecuhfhrohhmpefirhgvghcu mffjuceoghhrvghgsehkrhhorghhrdgtohhmqeenucggtffrrghtthgvrhhnpeeuleeltd ehkeeltefhleduuddvhfffuedvffduveegheekgeeiffevheegfeetgfenucffohhmrghi nhepkhgvrhhnvghlrdhorhhgnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpe hmrghilhhfrhhomhepghhrvghgsehkrhhorghhrdgtohhm X-ME-Proxy: Received: by mail.messagingengine.com (Postfix) with ESMTPA; Fri, 6 Aug 2021 02:28:42 -0400 (EDT) Date: Fri, 6 Aug 2021 08:28:39 +0200 From: Greg KH To: Jean Delvare Cc: linux-watchdog@vger.kernel.org, LKML , stable@vger.kernel.org, Jan Kiszka , Guenter Roeck , Wim Van Sebroeck , Michael Marley Subject: Re: Faulty commit "watchdog: iTCO_wdt: Account for rebooting on second timeout" Message-ID: References: <20210803165108.4154cd52@endymion> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210803165108.4154cd52@endymion> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 03, 2021 at 04:51:08PM +0200, Jean Delvare wrote: > Hi all, > > Commit cb011044e34c ("watchdog: iTCO_wdt: Account for rebooting on > second timeout") causes a regression on several systems. Symptoms are: > system reboots automatically after a short period of time if watchdog > is enabled (by systemd for example). This has been reported in bugzilla: > > https://bugzilla.kernel.org/show_bug.cgi?id=213809 > > Unfortunately this commit was backported to all stable kernel branches > (4.14, 4.19, 5.4, 5.10, 5.12 and 5.13). I'm not sure why that is the > case, BTW, as there is no Fixes tag and no Cc to stable@vger either. > And the fix is not trivial, has apparently not seen enough testing, > and addresses a problem that has a known and simple workaround. IMHO it > should never have been accepted as a stable patch in the first place. > Especially when the previous attempt to fix this issue already ended > with a regression and a revert. > > Anyway... After a glance at the patch, I see what looks like a nice > thinko: > > + if (p->smi_res && > + (SMI_EN(p) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN)) > > The author most certainly meant inl(SMI_EN(p)) (the register's value) > and not SMI_EN(p) (the register's address). Let me go revert this from the stable trees now, thanks for the report. greg k-h