4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
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@xxxxxxxxxx>
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Tested-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
Reviewed-by: Daniel P. Berrangé <berrange@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20221028062750.45451-1-mika.westerberg@xxxxxxxxxxxxxxx
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Signed-off-by: Wim Van Sebroeck <wim@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 930798bac582d..5ec52032117a7 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 */
--
2.40.1
