Storage: Fix hotplug not working on the first attempt

Author: Goldfish64

Changelog.md

@@ -13,6 +13,7 @@ MacHyperVSupport Changelog
 - Added ACPI fixup module to resolve ACPI issues on macOS 10.6 and older without SSDT
 - Removed requirement to force legacy mode on macOS 10.4 and 10.5, use the `ClearTaskSwitchBit` OpenCore Booter quirk instead
 - Added installer package for userspace components
+- Fixed storage hotplug not working on the first addition/removal of a disk
 
 #### v0.9.7
 - Fixed disks on a passed-in PCI device not being usable

MacHyperVSupport/Storage/HyperVStoragePrivate.cpp

@@ -39,7 +39,11 @@ static const HyperVStorageProtocol storageProtocols[] = {
 };
 
 bool HyperVStorage::wakePacketHandler(VMBusPacketHeader *pktHeader, UInt32 pktHeaderLength, UInt8 *pktData, UInt32 pktDataLength) {
-  return true;
+  //
+  // Only CompleteIO requests should wake sleeping threads.
+  //
+  HyperVStoragePacket *storPkt = (HyperVStoragePacket*) pktData;
+  return storPkt->operation == kHyperVStoragePacketOperationCompleteIO;
 }
 
 void HyperVStorage::handlePacket(VMBusPacketHeader *pktHeader, UInt32 pktHeaderLength, UInt8 *pktData, UInt32 pktDataLength) {