I'm facing such a problem. I've built a Windows kernel mode driver using WDK11, and, in order to pass Windows 11 WHQL, I need to use new memory allocating function ExAllocatePool2. The problem is, this driver will fail to load on Windows 7.
You know, Win7 does not have ExAllocatePool2, just like a user-mode EXE cannot find a new-era API in a system DLL on an older Windows OS, so the EXE fails to run.
For a user mode EXE, I can use LoadLibrary and GetProcAddress trick to dynamically detect that new-era API is not available at runtime, so that I can fall back to call older API.
I think the same idea applies to kernel mode, using RtlIsNtDdiVersionAvailable to probe for OS version, then call best available API from the system. But how to do real runtime dynamic linking to desired API?
Or, if there is a way to tell the system to ignore ExAllocatePool2 resolving errors when loading my .sys, the question is considered resolved as well.
In one word, the requirement is, I want to have a single binary to support all of Win11/Win10/Win7, and use new APIs on new OS.