Received: by 2002:a05:6a10:22f:0:0:0:0 with SMTP id 15csp594814pxk; Thu, 3 Sep 2020 07:51:06 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwb/GwtqcRlTTfuyfG7PlqCIbCC3qSVLsBlY/0Kwj6JgPWmKFmq//KUT+S9cH0pruTmq3T+ X-Received: by 2002:a17:906:edc4:: with SMTP id sb4mr2517139ejb.144.1599144666471; Thu, 03 Sep 2020 07:51:06 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1599144666; cv=none; d=google.com; s=arc-20160816; b=blPn2VLP3FB0/cC7Gnu2VoURmpo3TEkCMUyyT/kchPcWhHYluWqR3/1kQvOHNF8LTY IxV2ZRve/pGIA6GxT5io3VK3NwAAeWgcC5PyCwsd004+p+cPS1R1SvUzcwOwOa4OmM3V tj6SOFP1N7hdQsiPz0FWX/6aoalhCGcnfDZVBvmL+1J89iGB1WHZJMl85lcuW7umcQTL iL1cRwz/lFRkkOZYMUZ0E80Bki4Crna8PNH72nfGaZrQr0s0p0W0EJpsSBz3yuu+TxTg 8tpmOgUjZy6LFRUjk2PqUzj/7SXwHVQjL/EMnOoNRCaYWp9duDzOttmRVRe/LouzQo8v NVZQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :user-agent:organization:references:in-reply-to:date:cc:to:from :subject:message-id:dkim-signature; bh=l5bPZ71Mxm3f4LgVhP3Ovk9TkyFuRnOHfM8Zl7JMIto=; b=tkg9QQiTifZfCNUrWhiOj3vcHecXSYuawx97UWb4xmLSkKrz4CpBkJD59rVAccQOY1 1CqqaqJ4U5kLKSzA+pDuLkgOcnCbcJxDdvG+HQlGKNCLJqCrCEdCaJ5KpHwRTGfKQtgG ODzkbloTxZr1fbBfqCK96Gkh52AqtQgpufw787czwS63sT7QLzmDWAFFlo2i5ZdqY+Eq rmcAVPxXmBfk5e6ID8PpMwBXVMtEE0JCC6hkUofjMnOz8VpxxtKEWZjU+aOpQePvPsMi CM1wCtanp8pMnaeMdoUqSKSIRxjyB8vE9+SvsOEU5n/dAesHXAGN+RTFJWniiULE4/BW R1IA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@yadro.com header.s=mta-01 header.b=QJK0LQ9v; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=yadro.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id i6si1843675edy.469.2020.09.03.07.50.42; Thu, 03 Sep 2020 07:51:06 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@yadro.com header.s=mta-01 header.b=QJK0LQ9v; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=yadro.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729156AbgICOts (ORCPT + 99 others); Thu, 3 Sep 2020 10:49:48 -0400 Received: from mta-02.yadro.com ([89.207.88.252]:49518 "EHLO mta-01.yadro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729081AbgICOtc (ORCPT ); Thu, 3 Sep 2020 10:49:32 -0400 Received: from localhost (unknown [127.0.0.1]) by mta-01.yadro.com (Postfix) with ESMTP id EEB8E52195; Thu, 3 Sep 2020 13:22:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=yadro.com; h= content-transfer-encoding:mime-version:user-agent:content-type :content-type:organization:references:in-reply-to:date:date:from :from:subject:subject:message-id:received:received:received; s= mta-01; t=1599139370; x=1600953771; bh=maYMfRPvJLxeRFZ0FdSIdjuGM 4Bq3KUCafttH82y2bE=; b=QJK0LQ9v4Ikk9Epnuzf4HAoEjyr7yY5rGvshmE63J X/hzFwVZy3h57HSJ0jEMzNFfghfXldG5qo9zm8Kahd/vPS7i7DabhfMZOIpr+Lm5 TJr5gEOWpvSdIRFMscOV9p8G/wYFU2kNaH45ez42TAKwlnfYb5nKHPeDR6h8J8Ri L8= X-Virus-Scanned: amavisd-new at yadro.com Received: from mta-01.yadro.com ([127.0.0.1]) by localhost (mta-01.yadro.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id OWFpNQ-Y-vQ3; Thu, 3 Sep 2020 16:22:50 +0300 (MSK) Received: from T-EXCH-02.corp.yadro.com (t-exch-02.corp.yadro.com [172.17.10.102]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mta-01.yadro.com (Postfix) with ESMTPS id DA97E5141E; Thu, 3 Sep 2020 16:22:50 +0300 (MSK) Received: from localhost.localdomain (10.199.2.130) by T-EXCH-02.corp.yadro.com (172.17.10.102) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384_P384) id 15.1.669.32; Thu, 3 Sep 2020 16:22:50 +0300 Message-ID: <7a58bc3f80783170ecc38371aad7addc04397787.camel@yadro.com> Subject: Re: watchdog start on restart From: Ivan Mikhaylov To: Christophe Leroy , Guenter Roeck CC: Wim Van Sebroeck , , Date: Thu, 3 Sep 2020 16:26:18 +0300 In-Reply-To: References: <1721f170-95df-2451-e3af-6369e830afad@roeck-us.net> <2b14920abf9f430731ec11c1df6c0253185c7ce7.camel@yadro.com> Organization: YADRO Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.5 (3.32.5-1.fc30) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Originating-IP: [10.199.2.130] X-ClientProxiedBy: T-EXCH-01.corp.yadro.com (172.17.10.101) To T-EXCH-02.corp.yadro.com (172.17.10.102) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2020-09-03 at 13:13 +0200, Christophe Leroy wrote: > You want to start the watchdog just before calling 'reboot' but want to > make sure that the watchdog will not reset the board before all > userspace has shut down correctly ? Yes, just for an example, in the nature exists some aspeed2400/2500 board which has 2 watchdog devices and 2 spi flash memories. By default it starts from 1 spi flash. When watchdog triggers, on next boot, it's automatically starts from 2 flash, also you can manually switch from 1 spi flash to 2 with 2 watchdog device by trigger of it, like transparent reload from 1 spi flash side to 2. > But what is the purpose of the watchdog then, isn't it there to make > sure that the machine gets reboot within a given timeout anyway in case > some userspace takes too long to shut down ? Usually, yes. Thanks.