Backends stunk in wait event IPC/MessageQueueInternal

Hi, hackers

I had an incident on my Postgres 14 that queries hung in wait event
IPC / MessageQueueInternal, MessageQueueReceive.  It likes [1],
however, it doesn't have any discussions.

The process cannot be terminated by pg_terminate_backend(), although
it returns true.

Here is the call stack comes from pstack:

485073: /opt/local/pgsql/14/bin/postgres
 fffffb7fef216f4a ioctl     (d, d001, fffffb7fffdfa0e0)
 00000000008b8ec2 WaitEventSetWait  () + 112
 00000000008b920f WaitLatch () + 6f
 00000000008bf434 shm_mq_wait_internal () + 64
 00000000008bff74 shm_mq_receive () + 2b4
 000000000079fdc8 TupleQueueReaderNext () + 28
 000000000077d8ca gather_merge_readnext () + 13a
 000000000077db25 ExecGatherMerge () + 215
 0000000000790675 ExecNextLoop () + 175
 0000000000790675 ExecNextLoop () + 175
 000000000076267d standard_ExecutorRun () + fd
 fffffb7fe3965fbd pgss_executorRun () + fd
 00000000008df99b PortalRunSelect () + 1cb
 00000000008e0dcf PortalRun () + 17f
 00000000008ddacd PostgresMain () + 100d
 0000000000857f62 ServerLoop () + cd2
 0000000000858cee main () + 453
 00000000005ab777 _start_crt () + 87
 00000000005ab6d8 _start () + 18


Any suggestions?  Thanks in advance!

[1] https://www.postgresql.org/message-id/flat/E9FA92C2921F31408041863B74EE4C2001A479E590%40CCPMAILDAG03.cantab.local

-- 
Regrads,
Japin Li.
ChengDu WenWu Information Technology Co.,Ltd.