[PATCH AUTOSEL 4.19 038/209] watchdog: core: fix null pointer dereference when releasing cdev

[PATCH AUTOSEL 4.19 038/209] watchdog: core: fix null pointer dereference when releasing cdev

[Sasha Levin]

From: Wolfram Sang <wsa+renesas@sang-engineering.com>

[ Upstream commit 953b9dd7725bad55a922a35e75bff7bebf7b9978 ]

watchdog_stop() calls watchdog_update_worker() which needs a valid
wdd->wd_data pointer. So, when unregistering the cdev, clear the
pointers after we call watchdog_stop(), not before.

Fixes: bb292ac1c602 ("watchdog: Introduce watchdog_stop_on_unregister helper")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
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>
---
 drivers/watchdog/watchdog_dev.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
index ffbdc4642ea55..f6c24b22b37c0 100644
--- a/drivers/watchdog/watchdog_dev.c
+++ b/drivers/watchdog/watchdog_dev.c
@@ -1019,16 +1019,16 @@ static void watchdog_cdev_unregister(struct watchdog_device *wdd)
 		old_wd_data = NULL;
 	}
 
-	mutex_lock(&wd_data->lock);
-	wd_data->wdd = NULL;
-	wdd->wd_data = NULL;
-	mutex_unlock(&wd_data->lock);
-
 	if (watchdog_active(wdd) &&
 	    test_bit(WDOG_STOP_ON_UNREGISTER, &wdd->status)) {
 		watchdog_stop(wdd);
 	}
 
+	mutex_lock(&wd_data->lock);
+	wd_data->wdd = NULL;
+	wdd->wd_data = NULL;
+	mutex_unlock(&wd_data->lock);
+
 	hrtimer_cancel(&wd_data->timer);
 	kthread_cancel_work_sync(&wd_data->work);
 
-- 
2.20.1

[PATCH AUTOSEL 4.19 039/209] watchdog: renesas_wdt: stop when unregistering

[Sasha Levin]

From: Wolfram Sang <wsa+renesas@sang-engineering.com>

[ Upstream commit 14de99b44b34dbb9d0f64845b1cbb675e047767e ]

We want to go into a sane state when unregistering. Currently, it
happens that the watchdog stops when unbinding because of RuntimePM
stopping the core clock. When rebinding, the core clock gets reactivated
and the watchdog fires even though it hasn't been opened by userspace
yet. Strange scenario, yes, but sane state is much preferred anyhow.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
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>
---
 drivers/watchdog/renesas_wdt.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/watchdog/renesas_wdt.c b/drivers/watchdog/renesas_wdt.c
index d01efd342dc0c..62d9d3edcdf25 100644
--- a/drivers/watchdog/renesas_wdt.c
+++ b/drivers/watchdog/renesas_wdt.c
@@ -239,6 +239,7 @@ static int rwdt_probe(struct platform_device *pdev)
 	watchdog_set_drvdata(&priv->wdev, priv);
 	watchdog_set_nowayout(&priv->wdev, nowayout);
 	watchdog_set_restart_priority(&priv->wdev, 0);
+	watchdog_stop_on_unregister(&priv->wdev);
 
 	/* This overrides the default timeout only if DT configuration was found */
 	ret = watchdog_init_timeout(&priv->wdev, 0, &pdev->dev);
-- 
2.20.1

[PATCH AUTOSEL 4.19 040/209] watchdog: sama5d4: fix timeout-sec usage

[Sasha Levin]

From: Romain Izard <romain.izard.pro@gmail.com>

[ Upstream commit 2e0432f8f8ad11b4bd208445360220efa5b37d82 ]

When using watchdog_init_timeout to update the default timeout value,
an error means that there is no "timeout-sec" in the relevant device
tree node.

This should not prevent binding of the driver to the device.

Fixes: 976932e40036 ("watchdog: sama5d4: make use of timeout-secs provided in devicetree")
Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Reviewed-by: Marcus Folkesson <marcus.folkesson@gmail.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
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>
---
 drivers/watchdog/sama5d4_wdt.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index 255169916dbb6..1e93c1b0e3cfc 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -247,11 +247,7 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
 		}
 	}
 
-	ret = watchdog_init_timeout(wdd, wdt_timeout, &pdev->dev);
-	if (ret) {
-		dev_err(&pdev->dev, "unable to set timeout value\n");
-		return ret;
-	}
+	watchdog_init_timeout(wdd, wdt_timeout, &pdev->dev);
 
 	timeout = WDT_SEC2TICKS(wdd->timeout);
 
-- 
2.20.1

[PATCH AUTOSEL 4.19 041/209] watchdog: w83627hf_wdt: Support NCT6796D, NCT6797D, NCT6798D

[Sasha Levin]

From: Guenter Roeck <linux@roeck-us.net>

[ Upstream commit 57cbf0e3a0fd48e5ad8f3884562e8dde4827c1c8 ]

The watchdog controller on NCT6796D, NCT6797D, and NCT6798D is compatible
with the wtachdog controller on other Nuvoton chips.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/watchdog/w83627hf_wdt.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/watchdog/w83627hf_wdt.c b/drivers/watchdog/w83627hf_wdt.c
index 7817836bff554..4b9365d4de7a9 100644
--- a/drivers/watchdog/w83627hf_wdt.c
+++ b/drivers/watchdog/w83627hf_wdt.c
@@ -50,7 +50,7 @@ static int cr_wdt_csr;		/* WDT control & status register */
 enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
 	     w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
 	     w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792, nct6793,
-	     nct6795, nct6102 };
+	     nct6795, nct6796, nct6102 };
 
 static int timeout;			/* in seconds */
 module_param(timeout, int, 0);
@@ -100,6 +100,7 @@ MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
 #define NCT6792_ID		0xc9
 #define NCT6793_ID		0xd1
 #define NCT6795_ID		0xd3
+#define NCT6796_ID		0xd4	/* also NCT9697D, NCT9698D */
 
 #define W83627HF_WDT_TIMEOUT	0xf6
 #define W83697HF_WDT_TIMEOUT	0xf4
@@ -209,6 +210,7 @@ static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
 	case nct6792:
 	case nct6793:
 	case nct6795:
+	case nct6796:
 	case nct6102:
 		/*
 		 * These chips have a fixed WDTO# output pin (W83627UHG),
@@ -407,6 +409,9 @@ static int wdt_find(int addr)
 	case NCT6795_ID:
 		ret = nct6795;
 		break;
+	case NCT6796_ID:
+		ret = nct6796;
+		break;
 	case NCT6102_ID:
 		ret = nct6102;
 		cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
@@ -450,6 +455,7 @@ static int __init wdt_init(void)
 		"NCT6792",
 		"NCT6793",
 		"NCT6795",
+		"NCT6796",
 		"NCT6102",
 	};
 
-- 
2.20.1