watchdog: iTCO_wdt: Set NO_REBOOT if the watchdog is not already running

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 <berrange@redhat.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20221028062750.45451-1-mika.westerberg@linux.intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Mika Westerberg 2023-10-02 09:05:35 +02:00 committed by Greg Kroah-Hartman
parent c54a392fc7
commit 30055e020a

View File

@ -413,14 +413,18 @@ static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
return time_left; 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; 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)); val = inw(TCO1_CNT(p));
if (!(val & BIT(11))) if (!(val & BIT(11))) {
set_bit(WDOG_HW_RUNNING, &p->wddev.status); set_bit(WDOG_HW_RUNNING, &p->wddev.status);
return true;
}
return false;
} }
/* /*
@ -511,9 +515,6 @@ static int iTCO_wdt_probe(struct platform_device *pdev)
return -ENODEV; /* Cannot reset NO_REBOOT bit */ 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) { if (turn_SMI_watchdog_clear_off >= p->iTCO_version) {
/* /*
* Bit 13: TCO_EN -> 0 * Bit 13: TCO_EN -> 0
@ -565,7 +566,13 @@ static int iTCO_wdt_probe(struct platform_device *pdev)
watchdog_set_drvdata(&p->wddev, p); watchdog_set_drvdata(&p->wddev, p);
platform_set_drvdata(pdev, 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; /* Check that the heartbeat value is within it's range;
if not reset to the default */ if not reset to the default */