From patchwork Mon Oct 2 07:05:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 729235 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 952A8E784A5 for ; Mon, 2 Oct 2023 07:05:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235601AbjJBHFs (ORCPT ); Mon, 2 Oct 2023 03:05:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52254 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235684AbjJBHFq (ORCPT ); Mon, 2 Oct 2023 03:05:46 -0400 Received: from mta-64-227.siemens.flowmailer.net (mta-64-227.siemens.flowmailer.net [185.136.64.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCC8FB3 for ; Mon, 2 Oct 2023 00:05:41 -0700 (PDT) Received: by mta-64-227.siemens.flowmailer.net with ESMTPSA id 20231002070541d6d29fe43c22c73e16 for ; Mon, 02 Oct 2023 09:05:41 +0200 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; s=fm1; d=siemens.com; i=jan.kiszka@siemens.com; h=Date:From:Subject:To:Message-ID:MIME-Version:Content-Type:Content-Transfer-Encoding:Cc:References:In-Reply-To; bh=Rv4hUMKk2v8xsK+vx7AN42bMv3pzRiwWQuC3GPbDA5M=; b=XzO7tUyJCjKMbIYz4EzYkdkh47OhFL8qR5KHoIeuV6ZKX3zt1MDd2QsCeMtDm0XjZB04wN LMQ5APGDuZQc+1MyXbfrUt9k+K4sylUR8vqaIzclFNv6thSZjGYwpPvUhNePhQ26aTBQcih6 PDNt3gJqnmVShyxvjMBxbWK/asqek=; From: Jan Kiszka To: stable@vger.kernel.org, Mika Westerberg Cc: Wim Van Sebroeck , Guenter Roeck , linux-watchdog@vger.kernel.org, =?utf-8?q?Daniel_P_=2E_Berrang=C3=A9?= Subject: [PATCH 2/2] watchdog: iTCO_wdt: Set NO_REBOOT if the watchdog is not already running Date: Mon, 2 Oct 2023 09:05:40 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Flowmailer-Platform: Siemens Feedback-ID: 519:519-294854:519-21489:flowmailer Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org From: Mika Westerberg commit ef9b7bf52c2f47f0a9bf988543c577b92c92d15e upstream. Daniel reported that the commit 1ae3e78c0820 ("watchdog: iTCO_wdt: No need to stop the timer in probe") makes QEMU implementation of the iTCO watchdog not to trigger reboot anymore when NO_REBOOT flag is initially cleared using this option (in QEMU command line): -global ICH9-LPC.noreboot=false The problem with the commit is that it left the unconditional setting of NO_REBOOT that is not cleared anymore when the kernel keeps pinging the watchdog (as opposed to the previous code that called iTCO_wdt_stop() that cleared it). Fix this so that we only set NO_REBOOT if the watchdog was not initially running. Fixes: 1ae3e78c0820 ("watchdog: iTCO_wdt: No need to stop the timer in probe") Reported-by: Daniel P. Berrangé Signed-off-by: Mika Westerberg Tested-by: Daniel P. Berrangé Reviewed-by: Daniel P. Berrangé Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20221028062750.45451-1-mika.westerberg@linux.intel.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/iTCO_wdt.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c index 930798bac582..5ec52032117a 100644 --- a/drivers/watchdog/iTCO_wdt.c +++ b/drivers/watchdog/iTCO_wdt.c @@ -401,14 +401,18 @@ static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev) return time_left; } -static void iTCO_wdt_set_running(struct iTCO_wdt_private *p) +/* Returns true if the watchdog was running */ +static bool iTCO_wdt_set_running(struct iTCO_wdt_private *p) { u16 val; - /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is * enabled */ + /* Bit 11: TCO Timer Halt -> 0 = The TCO timer is enabled */ val = inw(TCO1_CNT(p)); - if (!(val & BIT(11))) + if (!(val & BIT(11))) { set_bit(WDOG_HW_RUNNING, &p->wddev.status); + return true; + } + return false; } /* @@ -486,9 +490,6 @@ static int iTCO_wdt_probe(struct platform_device *pdev) return -ENODEV; /* Cannot reset NO_REBOOT bit */ } - /* Set the NO_REBOOT bit to prevent later reboots, just for sure */ - p->update_no_reboot_bit(p->no_reboot_priv, true); - /* The TCO logic uses the TCO_EN bit in the SMI_EN register */ if (!devm_request_region(dev, p->smi_res->start, resource_size(p->smi_res), @@ -547,7 +548,13 @@ static int iTCO_wdt_probe(struct platform_device *pdev) watchdog_set_drvdata(&p->wddev, p); platform_set_drvdata(pdev, p); - iTCO_wdt_set_running(p); + if (!iTCO_wdt_set_running(p)) { + /* + * If the watchdog was not running set NO_REBOOT now to + * prevent later reboots. + */ + p->update_no_reboot_bit(p->no_reboot_priv, true); + } /* Check that the heartbeat value is within it's range; if not reset to the default */