Re: [Drbd-dev] [RFC][PATCH v2 04/31] timers: block: Use del_timer_shutdown() before freeing timer

[Guenter Roeck <linux@roeck-us.net>]

On 10/27/22 08:05, Steven Rostedt wrote:
> From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
> 
> Before a timer is freed, del_timer_shutdown() must be called.
> 

I also had to add the following, as you had already suggested.

Just changing blk_sync_queue() was insufficient; I had to add the call from
blk_release_queue() because otherwise blk_sync_queue() was not always called.

Thanks,
Guenter

---
diff --git a/block/blk-core.c b/block/blk-core.c
index 17667159482e..69b1daa2e91a 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -227,7 +227,7 @@ const char *blk_status_to_str(blk_status_t status)
   */
  void blk_sync_queue(struct request_queue *q)
  {
-       del_timer_sync(&q->timeout);
+       del_timer_shutdown(&q->timeout);
         cancel_work_sync(&q->timeout_work);
  }
  EXPORT_SYMBOL(blk_sync_queue);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e71b3b43927c..12a1e46536ed 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -769,6 +769,8 @@ static void blk_release_queue(struct kobject *kobj)

         percpu_ref_exit(&q->q_usage_counter);

+       blk_sync_queue(q);
+
         if (q->poll_stat)
                 blk_stat_remove_callback(q, q->poll_cb);
         blk_stat_free_callback(q->poll_cb);