Commit 9c921c22 authored Jun 30, 2011 by Lan Tianyu Committed by Len Brown Jul 14, 2011

ACPI / Battery: Resolve the race condition in the sysfs_remove_battery()

Use battery->lock in sysfs_remove_battery() to make
checking, removing, and clearing bat.dev atomic.
This is necessary because sysfs_remove_battery() may
be invoked concurrently from different paths.

    https://bugzilla.kernel.org/show_bug.cgi?id=35642



Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

parent 6e17fb6a

drivers/acpi/battery.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -573,11 +573,16 @@ static int sysfs_add_battery(struct acpi_battery *battery)

		static void sysfs_remove_battery(struct acpi_battery *battery)
		{
		if (!battery->bat.dev)
		mutex_lock(&battery->lock);
		if (!battery->bat.dev) {
		mutex_unlock(&battery->lock);
		return;
		}

		device_remove_file(battery->bat.dev, &alarm_attr);
		power_supply_unregister(&battery->bat);
		battery->bat.dev = NULL;
		mutex_unlock(&battery->lock);
		}

		/*