Comment 11 for bug 1745282

If bug https://bugs.launchpad.net/ubuntu/+source/linux-signed-hwe/+bug/1760272?comments=all is a duplicate of this one, then I made two useful tests:

- Kernel 4.15.0-041500-generic (from http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.15/) works fine.

- proposed kernel (linux-image-generic/artful-proposed,now 4.13.0.38.41 amd64) also freezes during boot.