Following the document, when running fedpkg local I get:

Error: Mismatches found in configuration files for x86_64 x86_64                                     
Found # CONFIG_STRICT_DEVMEM is not set, after generation, had CONFIG_STRICT_DEVMEM n in Source tree 
error: Bad exit status from /var/tmp/rpm-tmp.oUFeR9 (%prep)                        

I have added the option to kernel-local. So I expect this discrepancy. So is there any additional flag necessary to make this work without editing the individual config files?

P.S. Also I had huge troubles cloning https://src.fedoraproject.org/rpms/kernel.git. I was getting fetch-pack: unexpected disconnect while reading sideband packet. Eventually managed to clone by shallow cloning and then unshallowing the local tree. Basically splitting the work in multiple goes. Is the git repo experiencing troubles serving?