Comment # 46 on bug 913996 from Borislav Petkov

(In reply to Philip Brown from comment #35)
> 3) Install kernel of the day:
> zypper ar
> http://download.opensuse.org/repositories/Kernel:/openSUSE-13.2/standard \
>     Kernel:openSUSE-13.2
> zypper in --from Kernel:openSUSE-13.2 kernel-desktop
> 
> 4) Reboot
> 
>    *** At this point vboxsf no longer works.  Not sure why.
>        To get around problem I:
>        mount -t cifs //10.0.0.1/ds$ /media/llphil_d ....
>        and that worked.  Note that cifs is unstable if drive
>        is shared out from vbox.

I tried this here with your howto (thanks, btw) and it failed because
vbox has PAE disabled by default but the kernel is enabling it during
boot.

So I went and enabled it under Settings->System->Processor->Extended
Features [] Enable PAE/NX.

It boots fine then.

HTH.