gEdkiiVariableLockProtocolGuid

This protocol is intended for use as a means to mark a variable read-only after the event EFI_END_OF_DXE_EVENT_GUID is signaled.
Include/Protocol/VariableLock.h

PROTOCOL Information

PROTOCOL's Guid Name	PROTOCOL's Guid
gEdkiiVariableLockProtocolGuid	{ 0xcd3d0a05, 0x9e24, 0x437c, { 0xa8, 0x91, 0x1e, 0xe0, 0x53, 0xdb, 0x76, 0x38 }}

Refer to Header File

MdeModulePkg/Include/Protocol/VariableLock.h