1 Feb
2023
1 Feb
'23
1:38 p.m.
Issue #19395 has been updated by luke-gru (Luke Gruber).
ruby -v set to 3.2.0
Ubuntu 22.04, the issue seems to be calling `rb_native_mutex_destroy` on a locked mutex in
`ractor_free`.
Relevant part of the backtrace:
```
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(die+0x0) [0x7fc1374d0e5f]
/tmp/ruby-build.20230103230257.28392.jU9iPR/ruby-3.2.0/error.c:798
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(rb_bug)
/tmp/ruby-build.20230103230257.28392.jU9iPR/ruby-3.2.0/error.c:800
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(rb_bug_errno+0x43) [0x7fc137579223]
/tmp/ruby-build.20230103230257.28392.jU9iPR/ruby-3.2.0/error.c:829
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(rb_native_mutex_destroy+0x24)
[0x7fc137719a24]
/tmp/ruby-build.20230103230257.28392.jU9iPR/ruby-3.2.0/thread_pthread.c:603
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(ractor_free+0x11) [0x7fc137679991]
/tmp/ruby-build.20230103230257.28392.jU9iPR/ruby-3.2.0/ractor.c:235
/home/lukeg/.rbenv/versions/3.2.0/lib/libruby.so.3.2(run_final+0xf)
```
If instead you change `exit 0` to `exec "date"`, it doesn't crash. Maybe the
atfork hooks need to be changed to acquire locks in parent, unlock in child.
----------------------------------------
Bug #19395: Process forking within non-main Ractor causes segv
https://bugs.ruby-lang.org/issues/19395#change-101606
* Author: luke-gru (Luke Gruber)
* Status: Feedback
* Priority: Normal
* ruby -v: 3.2.0
* Backport: 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN
----------------------------------------
```ruby
def test_fork_in_ractor
r2 = Ractor.new do
pid = fork do
exit Ractor.count
end
pid
end
pid = r2.take
puts "Process #{Process.pid} waiting for #{pid}"
_pid, status = Process.waitpid2(pid) # stuck forever
if status.exitstatus != 1
raise "status is #{status.exitstatus}"
end
end
test_fork_in_ractor()
```
$ top # shows CPU usage is high for child process
--
https://bugs.ruby-lang.org/