system stuck on bios splash after reboot only

[farrok at t-online.de]

    Firstly, I couldn't find an answer for this specific problem, so I
    apologize when this is a common problem.

    Recently I installed FreeBSD again on a new laptop (Thinkpad T470
    20HES2SF00). On my desktop, the OS runs without problems with Xorg.

    I have chosen FreeBSD 12.0-CURRENT for that, because I need support for
    the iwm 8265 device + kabylake support via drm-next-kmod.

    Booting into the OS after the installation works (I use ZFS + GELI
    encryption), but when I reboot via reboot(8)
    <https://www.freebsd.org/cgi/man.cgi?query=reboot&sektion=8&manpath=freebsd-release-ports> 
     or shutdown -r now I'm stuck on the BIOS splash screen.

    Shutting down the computer and do a fresh boot works as expected, only
    rebooting doesn't work. The OS before (void linux, and well the
    preinstalled windows 10) didn't have that problem. Furthermore, the
    reboot is stuck only when fully logged in on the system before,
    rebooting from the FreeBSD bootloader works without problems.

    FreeBSD 11.1-RELEASE is stuck on reboot too.

    BIOS is version 1.30. Boot order is primary the SSD (I deactivated all
    others to test) UEFI boot, tried with/-out secure boot and old bios
    boot too.

    Is this a known problem? How can i fix it? Or how can I debug the
    problem, I would be thankful for some pointers.

    FreeBSD is pretty new to me, using it for some month as a second system
    on my desktop computer, but using GNU/Linux for over a decade and use
    the terminal extensively, so I hope I'm not completely incapable to fix
    the problem with some help!

    Hope it was understandable and thanks in advance!
     

 
copy of https://forums.freebsd.org/threads/63050/