KernSerialize16BitDD

This will acquire a special kernel spinlock.

Synopsis
VOID APIENTRY KernSerialize16BitDD(VOID);

Parameters
None.

Comments
It can be possible, according to the name, this has to be called before accessing a 16 bit driver. I wonder though, since you supposedly also have to adjust the stack pointer (KernThunkStackTo16), why both functions haven't been joined in a single call.