> We have a out of tree driver that maps huge pages through a file handle and > relies on -> huge_fault. It used to work in 5.19 kernels but 6.1 changed this > behaviour. > > I don’t think reverting the earlier behaviour of fault_path for huge pages should > impact kernel negatively. > > Do you think we can restore this earlier behaviour of kernel to allow page fault > for huge pages via ->huge_fault. That seems reasonable to me. I think using the existence of a ->huge_fault() handler as a predicate to return "true" makes sense to me. The "normal" flow for file-backed memory along fault path still needs to return "false", so that we correctly fallback to ->fault() handler. Unless there are objections, I can do that in a v2.
