From 0fd13791feb649c2e0e5c855eaf7c07864535578 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Fri, 28 Oct 2022 09:27:50 +0300 Subject: [PATCH] watchdog: iTCO_wdt: Set NO_REBOOT if the watchdog is not already running MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit [ Upstream commit ef9b7bf52c2f47f0a9bf988543c577b92c92d15e ] 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 Signed-off-by: Sasha Levin --- 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 34693f1..e937b4d 100644 --- a/drivers/watchdog/iTCO_wdt.c +++ b/drivers/watchdog/iTCO_wdt.c @@ -423,14 +423,18 @@ 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; } /* @@ -518,9 +522,6 @@ 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); - if (turn_SMI_watchdog_clear_off >= p->iTCO_version) { /* * Bit 13: TCO_EN -> 0 @@ -572,7 +573,13 @@ 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 */ -- 2.7.4