[PATCH v2 3/3] regulator: core: Keep regulators-list locked while traversing the list

[Dmitry Osipenko]

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 <dig...@gmail.com>
---
 drivers/regulator/core.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a3ab419a3aa6..7bb5bc16babf 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -4971,7 +4971,9 @@ 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);
@@ -4979,8 +4981,9 @@ 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);
 
@@ -5313,6 +5316,8 @@ 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 {
@@ -5339,6 +5344,8 @@ 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)
-- 
2.19.1