[PATCH v7 03/20] reboot: Print error message if restart handler has duplicated priority

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Add sanity check which ensures that there are no two restart handlers
registered using the same priority. This requirement will become mandatory
once all drivers will be converted to the new API and such errors will be
fixed.

Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
---
 kernel/reboot.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/kernel/reboot.c b/kernel/reboot.c
index ed4e6dfb7d44..acdae4e95061 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -182,6 +182,21 @@ static ATOMIC_NOTIFIER_HEAD(restart_handler_list);
  */
 int register_restart_handler(struct notifier_block *nb)
 {
+	int ret;
+
+	ret = atomic_notifier_chain_register_unique_prio(&restart_handler_list, nb);
+	if (ret != -EBUSY)
+		return ret;
+
+	/*
+	 * Handler must have unique priority. Otherwise call order is
+	 * determined by registration order, which is unreliable.
+	 *
+	 * This requirement will become mandatory once all drivers
+	 * will be converted to use new sys-off API.
+	 */
+	pr_err("failed to register restart handler using unique priority\n");
+
 	return atomic_notifier_chain_register(&restart_handler_list, nb);
 }
 EXPORT_SYMBOL(register_restart_handler);
-- 
2.35.1




[Index of Archives]     [LKML Archive]     [Linux ARM Kernel]     [Linux ARM]     [Git]     [Yosemite News]     [Linux SCSI]     [Linux Hams]

  Powered by Linux