LINUX_VERSION_EXTENSION is now appended to various kernel package names. It did not used to be. opkg-build will not accept capital letters or underscores in package names. To reproduce, change the variable in linux-yocto.inc to include "Yocto" instead of "yocto", specify ipk packaging in local.conf, and build linux-yocto. This could be considered a regression since the contents of the variable did not used to matter for packaging purposes. Tests made from poky cloned (master branch) on 2-May-2017.
Confirmed that with a Capitalized letter in the package name that IPK will fail during the package_ipk task, but DEB will not. Both DEB and IPK will fail with an '_' in the name. So, we should add a sanity test for at least '_' (and other known symbols) in the package name. Do we need to fix ipk to accept UpperCase letters in the package name, is that even feasible?
CCing the opkg maintainer. Alejandreo: why does opkg refuse to build packages with uppercase names? (dpkg and rpm don't care)
I believe opkg is following debian policy: "Package names (both source and binary, see Package, Section 5.6.7) must consist only of lower case letters (a-z), digits (0-9), plus (+) and minus (-) signs, and periods (.). They must be at least two characters long and must start with an alphanumeric character." [1] not sure which tool OE is using for building debian or why it's not following the policy....but the policy kinda make sense to me: it prevents having repos with 2 packages with the same name, but with different capitalization. [1] https://www.debian.org/doc/debian-policy/ch-controlfields.html#s-f-Source
I'm fine with following the sensible Debian policy. Thanks for the explanation. The problem we encountered was due to an upper case LINUX_VERSION_EXTENSION as Joe explained.