From 40e105042a4bec83ad8bc39e54edde2caf68d6a8 Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Sat, 12 Jul 2025 11:18:05 +1200 Subject: [PATCH] Fix stale idle flag when IO workers exit. Otherwise we could choose a worker that has exited and crash while trying to wake it up. Back-patch to 18. Reported-by: Tomas Vondra Reported-by: Andres Freund Discussion: https://postgr.es/m/t5aqjhkj6xdkido535pds7fk5z4finoxra4zypefjqnlieevbg%40357aaf6u525j --- src/backend/storage/aio/method_worker.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/backend/storage/aio/method_worker.c b/src/backend/storage/aio/method_worker.c index 36be179678d..6454987e9f5 100644 --- a/src/backend/storage/aio/method_worker.c +++ b/src/backend/storage/aio/method_worker.c @@ -172,6 +172,7 @@ pgaio_choose_idle_worker(void) /* Find the lowest bit position, and clear it. */ worker = pg_rightmost_one_pos64(io_worker_control->idle_worker_mask); io_worker_control->idle_worker_mask &= ~(UINT64_C(1) << worker); + Assert(io_worker_control->workers[worker].in_use); return worker; } @@ -316,6 +317,7 @@ pgaio_worker_die(int code, Datum arg) Assert(io_worker_control->workers[MyIoWorkerId].in_use); Assert(io_worker_control->workers[MyIoWorkerId].latch == MyLatch); + io_worker_control->idle_worker_mask &= ~(UINT64_C(1) << MyIoWorkerId); io_worker_control->workers[MyIoWorkerId].in_use = false; io_worker_control->workers[MyIoWorkerId].latch = NULL; LWLockRelease(AioWorkerSubmissionQueueLock); -- 2.39.5