hwmon: (adt7470) Fix warning on module removal

BugLink: https://bugs.launchpad.net/bugs/1978240
commit 7b2666ce445c700b8dcee994da44ddcf050a0842 upstream.

When removing the adt7470 module, a warning might be printed:

do not call blocking ops when !TASK_RUNNING; state=1
set at [<ffffffffa006052b>] adt7470_update_thread+0x7b/0x130 [adt7470]

This happens because adt7470_update_thread() can leave the kthread in
TASK_INTERRUPTIBLE state when the kthread is being stopped before
the call of set_current_state(). Since kthread_exit() might sleep in
exit_signals(), the warning is printed.
Fix that by using schedule_timeout_interruptible() and removing
the call of set_current_state().
This causes TASK_INTERRUPTIBLE to be set after kthread_should_stop()
which might cause the kthread to exit.

Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Fixes: 93cacfd41f82 (hwmon: (adt7470) Allow faster removal)
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Tested-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220407101312.13331-1-W_Armin@gmx.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/hwmon/adt7470.c b/drivers/hwmon/adt7470.c
index fb6d14d213a18c8595e8111f6c0c72890e1c0d61..c67cd037a93fde44ee7e4d9d0fc1e53b642c27a6 100644 (file)
--- a/drivers/hwmon/adt7470.c
+++ b/drivers/hwmon/adt7470.c
@@ -19,6 +19,7 @@
 #include <linux/log2.h>
 #include <linux/kthread.h>
 #include <linux/regmap.h>
+#include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/util_macros.h>
 
@@ -294,11 +295,10 @@ static int adt7470_update_thread(void *p)
                adt7470_read_temperatures(data);
                mutex_unlock(&data->lock);
 
-               set_current_state(TASK_INTERRUPTIBLE);
                if (kthread_should_stop())
                        break;
 
-               schedule_timeout(msecs_to_jiffies(data->auto_update_interval));
+               schedule_timeout_interruptible(msecs_to_jiffies(data->auto_update_interval));
        }
 
        return 0;