From 56d35bf409d54bc82cdf92aa7f1be88b27899d2a Mon Sep 17 00:00:00 2001
From: kd-11 <karokidii@gmail.com>
Date: Sun, 25 Aug 2024 20:51:58 +0300
Subject: [PATCH] Fix crash in JIT when compiling LLVM blocks

---
 Utilities/JITASM.cpp | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Utilities/JITASM.cpp b/Utilities/JITASM.cpp
index aebfbcd272..b1d227fc15 100644
--- a/Utilities/JITASM.cpp
+++ b/Utilities/JITASM.cpp
@@ -185,8 +185,13 @@ static u8* add_jit_memory(usz size, usz align)
 	if (olda != newa) [[unlikely]]
 	{
 #ifndef CAN_OVERCOMMIT
-		// Commit more memory
-		utils::memory_commit(pointer + olda, newa - olda, Prot);
+		// Commit more memory.
+		// NOTE: Calling memory commit in parallel on the same addresses can throw a permission error.
+		{
+			static std::mutex mcommit_lock;
+			std::lock_guard lock(mcommit_lock);
+			utils::memory_commit(pointer + olda, newa - olda, Prot);
+		}
 #endif
 		// Acknowledge committed memory
 		Ctr.atomic_op([&](u64& ctr)