RancherOS as Xen DomU in PV (paravirtualization) mode

I’m deploing some VM`s in a Xen server. I had success running the virtual machines in HVM (fully virtualized) mode.

But there is a performance hit running a VM in that mode. So I’m trying to run in PV (paravirtualization) mode. To do so, I tried to setup some parameters in the .cfg (link) file that describe the Xen VM like kernel parameter without success.

Then, I need some help.

Thank you!