regulator: core: Keep regulators-list locked while traversing the list
authorDmitry Osipenko <digetx@gmail.com>
Sun, 18 Nov 2018 21:56:19 +0000 (00:56 +0300)
committerMark Brown <broonie@kernel.org>
Mon, 19 Nov 2018 12:33:19 +0000 (12:33 +0000)
It's unlikely that regulators may disappear/appear while regulators
debug-summary is being prepared, but let's be consistent and avoid that
situation.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
drivers/regulator/core.c

index e46e53a..fd237bc 100644 (file)
@@ -4936,7 +4936,9 @@ void regulator_unregister(struct regulator_dev *rdev)
                        regulator_disable(rdev->supply);
                regulator_put(rdev->supply);
        }
+
        mutex_lock(&regulator_list_mutex);
+
        debugfs_remove_recursive(rdev->debugfs);
        flush_work(&rdev->disable_work.work);
        WARN_ON(rdev->open_count);
@@ -4944,8 +4946,9 @@ void regulator_unregister(struct regulator_dev *rdev)
        unset_regulator_supplies(rdev);
        list_del(&rdev->list);
        regulator_ena_gpio_free(rdev);
-       mutex_unlock(&regulator_list_mutex);
        device_unregister(&rdev->dev);
+
+       mutex_unlock(&regulator_list_mutex);
 }
 EXPORT_SYMBOL_GPL(regulator_unregister);
 
@@ -5278,6 +5281,8 @@ static void regulator_summary_lock(struct ww_acquire_ctx *ww_ctx)
        struct regulator_dev *old_contended_rdev = NULL;
        int err;
 
+       mutex_lock(&regulator_list_mutex);
+
        ww_acquire_init(ww_ctx, &regulator_ww_class);
 
        do {
@@ -5304,6 +5309,8 @@ static void regulator_summary_unlock(struct ww_acquire_ctx *ww_ctx)
        class_for_each_device(&regulator_class, NULL, NULL,
                              regulator_summary_unlock_one);
        ww_acquire_fini(ww_ctx);
+
+       mutex_unlock(&regulator_list_mutex);
 }
 
 static int regulator_summary_show_roots(struct device *dev, void *data)