Comment # 20 on bug 956526 from Jan Beulich

(In reply to boo35 boo35 from comment #19)
> removing /mapbs
> adding efi=no-rs
> 
> so that
> 
>  cat /proc/cmdline 
>   root=UUID= ... efi=no-rs 
> 
> returns the PANIC.
> 
> I.e., /mapbs remediates the PANIC; efi=no-rs does not.

If the option shows up in /proc/cmdline, the you added it to the kernel options
instead of the hypervisor ones.