Virtualization
Running 64KiB guests on 4KiB hosts
When trying to start a VM on a host running with 4KiB pages, you might see the following error message:
qemu-system-ppc64: Can't support 64 kiB guest pages with 4 kiB host pages with this KVM implementation
There is an easy workaround for this. If running QEMU directly, add the argument -machine pseries,cap-hpt-max-page-size=4096
. If running QEMU via libvirt, add the following section[1] to the guest's libvirt XML (via virsh edit [guest name]
or the XML tab in virt-manager):
<features> <hpt> <maxpagesize unit='KiB'>4</maxpagesize> </hpt> </features>
Nested KVM
In order to be able to run nested KVM, two things must be satisfied:
- The
kvm_hv
kernel module must be loaded with thenested=1
module argument - The L1 guest must be started with
-machine pseries,cap-nested-hv=on
as argument to qemu. If running qemu via libvirt, add the following XML fragment to the XML:
<features> <nested-hv state="on"/> </features>