Comment 23 for bug 1760796

@Billy thanks for the Xenial xl2tpd test package.

I setup an Ubuntu 16.04.4 VM which came with kernel 4.13.0-36-generic and did an apt update followed by an apt upgrade and it installed kernel 4.15.0-29-generic. I didn't know the proper way to downgrade to kernel 4.4, so manually downloaded and installed the following :

    linux-headers-4.4.0-124_4.4.0-124.148_all.deb
    linux-headers-4.4.0-124-generic_4.4.0-124.148_amd64.deb
    linux-image-4.4.0-124-generic_4.4.0-124.148_amd64.deb

Following is a summary of the tests performed, first with unpatched xl2tpd followed by the test PPA xl2tpd.

Ubuntu 16.04.4 with xl2tpd-1.3.6+dfsg-4ubuntu0.16.04.1 :

* didn't check kernel 4.4.0-124-generic.

* kernel 4.13.0-36-generic - works as expected.

* kernel 4.15.0-29-generic - results in following error as expected :

  xl2tpd[2189]: udp_xmit failed ... with err=-1:No such device

Ubuntu 16.04.4 upgrade to xl2tpd-1.3.6+dfsg-4ubuntu0.16.04.1+lp1760796 :

* kernel 4.4.0-124-generic - works!

* kernel 4.13.0-36-generic - works!

* kernel 4.15.0-29-generic - works!

So things look okay to me in regards to xenial.