From 073e043b028fb890da0dd3a7b7d0196847ba0f56 Mon Sep 17 00:00:00 2001
From: Jeroen van Rijn <Kelimion@users.noreply.github.com>
Date: Mon, 13 Oct 2025 02:59:57 +0200
Subject: [PATCH] Fix hang, courtesy of cloin.

---
 src/threading.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/threading.cpp b/src/threading.cpp
index 84f09912d..02e6de14b 100644
--- a/src/threading.cpp
+++ b/src/threading.cpp
@@ -480,6 +480,7 @@ void rwlock_acquire_upgrade(RWSpinLock *l) {
 }
 void rwlock_release_upgrade(RWSpinLock *l) {
 	l->bits.fetch_add(-RWLOCK_UPGRADED, std::memory_order_acq_rel);
+	futex_signal(&l->bits);
 }
 
 bool rwlock_try_release_upgrade_and_acquire_write(RWSpinLock *l) {