upstream kernel already has sane built in default config, and I've seen a few bugs where genkernel doing it the hard way is causing problems. Suggest letting genkernel use whatever the kernel's own default config is. Reproducible: Always
Upstream config is not going to enable NEARLY enough drivers for a usable "genkernel all" for most users. Genkernel's configs need reworking, but I'm fairly sure that using upstream configs is NOT going to be the solution.
how about "allyesconfig"?
What about maintaining the genkernel specific portion as simply a diff against the upstream default? Might make it easier to maintain when upstream changes.
This is already done with the newer kernel-generic-config + arch-config stuff.