Does RHEV support SR-IOV and Nested VM？

1) I am failed to enable IOMMU on the kernel due to no permission to the /etc/sysconfig/grub. Even I follow the guide on https://access.redhat.com/solutions/769643, SR-IOV still doesn't work.

2) May I know if RHEV supports nested VM. I add vmx in the cpu feature of the vm xml file on the RHEL and works fine via virsh tool . No idea how to configure in RHEV which doesn't hold the xml of the vm.

Thanks a lot for the support.