I have just built a Threadripper 3960X system as my new desktop machine, and as such wanted to use a more up to date kernel than is provided in Ubuntu 19.10 by default. Currently that means 5.4.6-generic. I also have installed the linux-5.4.6-headers and build-essential.

After installing the kernel and rebooting, I noticed I can no longer connect to Mullvad using WireGuard. On further investigation the DKMS module is giving the following error during build:

> Building initial module for 5.4.6-050406-generic
> ERROR (dkms apport): kernel package linux-headers-5.4.6-050406-generic is not supported
> Error! Bad return status for module build on kernel: 5.4.6-050406-generic (x86_64)
> Consult /var/lib/dkms/wireguard/0.0.20190913/build/make.log for more information.
> dpkg: error processing package wireguard-dkms (--configure):
>  installed wireguard-dkms package post-installation script subprocess returned error exit status 10
> Errors were encountered while processing:
>  wireguard-dkms
> E: Sub-process /usr/bin/dpkg returned an error code (1)


Does anyone have any ideas? The error log was somewhat vague (to my uneducated eyes).

> DKMS make.log for wireguard-0.0.20190913 for kernel 5.4.6-050406-generic (x86_64)
> Mon 23 Dec 00:18:36 GMT 2019
> make: Entering directory '/usr/src/linux-headers-5.4.6-050406-generic'
>   AR      /var/lib/dkms/wireguard/0.0.20190913/build/built-in.a
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/main.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/noise.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/device.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/peer.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/timers.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/queueing.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/send.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/receive.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/socket.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/peerlookup.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/allowedips.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/ratelimiter.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/cookie.o
>   PERLASM /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/chacha20/chacha20-x86_64.S
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/netlink.o
>   PERLASM /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/poly1305/poly1305-x86_64.S
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/chacha20/chacha20.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/poly1305/poly1305.o
>   AS [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/blake2s/blake2s-x86_64.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/chacha20poly1305.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/blake2s/blake2s.o
>   CC [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/curve25519/curve25519.o
>   AS [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/poly1305/poly1305-x86_64.o
>   AS [M]  /var/lib/dkms/wireguard/0.0.20190913/build/crypto/zinc/chacha20/chacha20-x86_64.o
> /var/lib/dkms/wireguard/0.0.20190913/build/socket.c: In function ‘send6’:
> /var/lib/dkms/wireguard/0.0.20190913/build/socket.c:145:20: error: ‘const struct ipv6_stub’ has no member named ‘ipv6_dst_lookup’; did you mean ‘ipv6_dst_lookup_flow’?
>   145 |   ret = ipv6_stub->ipv6_dst_lookup(sock_net(sock), sock, &dst,
>       |                    ^~~~~~~~~~~~~~~
>       |                    ipv6_dst_lookup_flow
> make[1]: *** [scripts/Makefile.build:266: /var/lib/dkms/wireguard/0.0.20190913/build/socket.o] Error 1
> make[1]: *** Waiting for unfinished jobs....
> make: *** [Makefile:1652: /var/lib/dkms/wireguard/0.0.20190913/build] Error 2
> make: Leaving directory '/usr/src/linux-headers-5.4.6-050406-generic'


I’ve rolled back to the official kernel for now but with the CPU being so new that’s not ideal.
Thanks in advance.

Lee Yates