Home / server / Questions / 1095142
In Process
pefu
Asked: 2022-03-03 01:07:36 +0800 CST

Xen hypervisor: What does the acronym RMRR mean in "(XEN) [VT-D] It's risky to assign" ... "with shared RMRR at"? What are the risks?

  • 772

I'm running Qubes-OS 4.1.0 While looking through the /var/log/xen/console/hypervisor.log I stumbled over the following messages:

...
(XEN) [VT-D] It's risky to assign 0000:00:14.0 with shared RMRR at c9f42000 for Dom40.
(XEN) [VT-D] It's risky to assign 0000:00:1d.0 with shared RMRR at c9f42000 for Dom40.

In my case those PCI devices in question are USB controllers. They are handled by a VM called sys-usb in order to protect the bare metal carrier system from the risks of any malicious USB device being plugged in.

My questions are: What is the meaning of the acronym RMRR in this context? And what are the risks involved with this so called "shared RMRR"?

xen security usb fedora-32

0 Answers