Comment 15 for bug 1783267

@ubuntu-kernel-bot uploaded logs as requested
Since I can't boot with kernel 4.15, these logs are from my running system with 4.13.

I've just upgraded virtualbox-guest-dkms-hwe, virtualbox-guest-utils-hwe and virtualbox-guest-x11-hwe from version 5.1.34-dfsg-0ubuntu1.16.04.2 to 5.1.38-dfsg-0ubuntu1.16.04.1, but the problem still persists:

Setting up virtualbox-guest-utils-hwe (5.1.38-dfsg-0ubuntu1.16.04.1) ...
Installing new version of config file /etc/init.d/virtualbox-guest-utils-hwe ...
Setting up virtualbox-guest-x11-hwe (5.1.38-dfsg-0ubuntu1.16.04.1) ...
Setting up virtualbox-guest-dkms-hwe (5.1.38-dfsg-0ubuntu1.16.04.1) ...
Loading new virtualbox-guest-5.1.38 DKMS files...
Building for 4.13.0-45-generic and 4.15.0-29-generic
Building initial module for 4.13.0-45-generic
Done.

vboxguest:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/4.13.0-45-generic/updates/dkms/

vboxsf.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/4.13.0-45-generic/updates/dkms/

vboxvideo.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/4.13.0-45-generic/updates/dkms/

depmod....

DKMS: install completed.
Building initial module for 4.15.0-29-generic
Done.

vboxguest:
Running module version sanity check.
Error! Module version 5.1.38_Ubuntu for vboxguest.ko
is not newer than what is already found in kernel 4.15.0-29-generic (5.2.8_KernelUbuntu).
You may override by specifying --force.

vboxsf.ko:
Running module version sanity check.
Error! Module version 5.1.38_Ubuntu for vboxsf.ko
is not newer than what is already found in kernel 4.15.0-29-generic (5.2.8_KernelUbuntu).
You may override by specifying --force.

vboxvideo.ko:
Running module version sanity check.
 - Original module
 - Installation
   - Installing to /lib/modules/4.15.0-29-generic/updates/dkms/

depmod....

DKMS: install completed.