From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-rt-users-owner@vger.kernel.org Received: from krieglstein.org ([176.28.13.145]:59030 "EHLO krieglstein.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726235AbeITOKu (ORCPT ); Thu, 20 Sep 2018 10:10:50 -0400 From: Tim Sander Subject: Re: [BUG] dw_wdt watchdog on linux-rt 4.18.5-rt4 not triggering Date: Thu, 20 Sep 2018 10:18:33 +0200 Message-ID: <2133238.jDSj0JK9k1@dabox> In-Reply-To: <714e73d5-f7ce-bdcf-b7fd-fc9f02b12693@roeck-us.net> References: <73d0tbdjqz.fsf@pengutronix.de> <714e73d5-f7ce-bdcf-b7fd-fc9f02b12693@roeck-us.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-rt-users-owner@vger.kernel.org List-ID: To: Guenter Roeck Cc: Steffen Trumtrar , linux-watchdog@vger.kernel.org, Wim Van Sebroeck , Christophe Leroy , linux-rt-users@vger.kernel.org Hi I am also seeing this problem. Am Dienstag, 18. September 2018, 15:46:15 CEST schrieb Guenter Roeck: > Please not only describe what you are doing, but also provide the complete > context. Specifically, > - Did this ever work ? I have not found a working kernel version. > If yes, what are working kernel versions ? I have tried different kernel version which where *not* working: patch-4.11.12-rt15 (with some Altera/Intel driver patches) 4.16.8-rt3 4.18-rc8-rt1 4.18.7-rt5 (with adxl372 iio patches and denali nand race fix reported on mainline) > - Is the watchdog device open ? Good point: The bootloader arms the watchdog. Then WATCHDOG_HANDLE_BOOT_ENABLED is enabled in kernel. But i forgot to let usermode take over. > - Does it make a difference if it is ? If i set RuntimeWatchdogSec=30 in /etc/systemd/system.conf (i.e. enable usermode watchdog) the problem seems to go away (at least i didn't had a reboot dony with my short testruns by now). > - What is the configured watchdog timeout (both from BIOS/ROMMON and in > Linux) ? 30s So to wrap up: i have the suspicion that the option WATCHDOG_HANDLE_BOOT_ENABLED without usermode taking over in Linux leads to some strange behaviour with preempt rt? Best regards Tim