Nixpkgs: kernel 5.4.29 broke wireguard

[ajs124]

Describe the bug
The stable kernel update to 5.4.29 in 7bae57f24921a88e68d16b2e66df661963b3d733 broke the wireguard build. This is an upstream issue, which is potentially fixed by the patch in this email.

Upstream has not issued a new release yet.

There is also this now, which is a "real backport" of wireguard from 5.6, vs. the compat source we are using now. See this announcement.

To Reproduce
Steps to reproduce the behavior:

1. Try to build wireguard against 5.4.29
2. observe build failure

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
- linuxPackages
# a list of nixos modules affected by the problem
module:
- services/networking/wireguard.nix

cc @NeQuissimus @Ma27

[ajs124]

There is an upstream release now, see https://lists.zx2c4.com/pipermail/wireguard/2020-April/005237.html

[Ma27]

Ah, great, currently building 5.4.29 and just wanted to suggest to simply apply the patch :)
Will test this release and publish the update now.

[Ma27]

Also backported as e39c7b99c8247b7b08efd08c7a7493be2395f364.

[ajs124]

Seems like this wasn't backported to 19.09, but that's also broken, if you're using a 5.4 (e.g. linuxPackages_latest) kernel.

[Ma27]

Thx, backported to 19.09 as 7a429e731e3fa3dcf756a7939b23a74ba56215cf.