From 6c4b04de5cba36077f86b08d54c4c316f3df1d87 Mon Sep 17 00:00:00 2001
From: Koichi Sasada <ko1@atdot.net>
Date: Mon, 18 Dec 2023 21:40:43 +0900
Subject: [PATCH] clear `sched->lock_onwer` at fork

`sched->lock_owner` can be non-NULL at fork because the timer thread
can acquire the lock while forking. `lock_owner` information is for
debugging, so we only need to clear it at fork.

I hope this patch fixes the following assertion failure:
```
thread_pthread.c:354:thread_sched_lock_:sched->lock_owner == NULL
```
---
 thread_pthread.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/thread_pthread.c b/thread_pthread.c
index 64b636ec08..e7e827793b 100644
--- a/thread_pthread.c
+++ b/thread_pthread.c
@@ -1129,6 +1129,11 @@ void
 rb_thread_sched_init(struct rb_thread_sched *sched, bool atfork)
 {
     rb_native_mutex_initialize(&sched->lock_);
+
+#if VM_CHECK_MODE
+    sched->lock_owner = NULL;
+#endif
+
     ccan_list_head_init(&sched->readyq);
     sched->readyq_cnt = 0;