From b03dc847f5bad1bffe954245068b10e4b2bce8ac Mon Sep 17 00:00:00 2001
From: Justin Becker <jubecker@nvidia.com>
Date: Wed, 2 Sep 2026 17:06:23 -0700
Subject: [PATCH] Fix syscall regression

---
 Source/Windows/ARM64EC/Module.S | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Source/Windows/ARM64EC/Module.S b/Source/Windows/ARM64EC/Module.S
index f76f92d77..4c18172ea 100644
--- a/Source/Windows/ARM64EC/Module.S
+++ b/Source/Windows/ARM64EC/Module.S
@@ -108,11 +108,15 @@ ExitFunctionSuspendPoint:
   Name:; \
     adrp x16, WineSyscallDispatcher; \
     ldr x16, [x16, HASH:lo12:WineSyscallDispatcher]; \
+    cbz x16, 1f; \
     mov x9, x30; \
     adrp x8, WineIdName; \
     ldr x8, [x8, HASH:lo12:WineIdName]; \
     blr x16; \
     ret; \
+  1:; \
+    svc HASH WindowsId; \
+    ret
 
   // Allows for continuing from a full native context, as the NTDLL NtContinue export takes in an x64 context with EC and
   // the conversion to that loses the ARM64EC ABI-disallowed registers that FEX uses.