Virtual & unusual hardware

Virtio random-source function over modern PCI

A guest random-source device imports bytes from a host-provided backend.

On this page
  1. Overview & identity
  2. Driver & binding
  3. Firmware
  4. Read-only diagnostics
  5. Limitations & related issues
  6. References

Overview & identity

The checked modern PCI rule maps 1af4:1044 to virtio type 4 (rng). This is a virtual function identity, not the host hardware model. Transitional PCI IDs use a different subsystem-ID rule and are deliberately not inferred here.

Curated identifiers
pci 1af4:1044

A numeric match establishes a candidate family within the reviewed evidence. Marketing names, board variants, subsystem conditions and successful operation remain separate questions.

Driver & binding

virtio_rng registers the function as a hardware-RNG provider after virtio type 4 is discovered. The RNG framework’s available/current provider is separate from the PCI transport’s binding and from the kernel random pool’s internal state. lspci can therefore correctly report virtio-pci while the child function is bound to virtio_rng.

  • virtio_pci — kernel driver/module candidate
  • virtio_rng — kernel driver/module candidate

Detected, bound, operational: learn the difference

Firmware

No host payload established here

No external firmware filename was established in the checked driver path. This does not describe firmware stored inside the device.

Inspect firmware packaging on your distribution

Read-only diagnostics

Run one displayed command at a time. Replace uppercase placeholders with the affected device, interface or module from your own output. Commands are never executed here. Read-only output can still contain private identifiers.

Inspect the PCI function and binding

lspci -nnk -s BDF

Replace BDF with the complete address, for example 0000:00:14.0. This read-only query needs pciutils and normally no sudo. “Kernel driver in use” is observed binding; “Kernel modules” lists candidates.

Inspect the virtio child function driver

ls -l /sys/bus/pci/devices/BDF/virtio*/driver

Replace BDF with the full observed PCI address. Read the child driver link without sudo; virtio_pci is the PCI transport, while this link belongs to the function driver. A missing child or link means that this layer was not observed.

Read registered RNG provider names

cat /sys/class/misc/hw_random/rng_available

Read provider metadata without sudo and without consuming /dev/hwrng. A virtio provider name shows registration, not a security assessment or proof that it is the active selected source.

Limitations & related issues

A virtual RNG label does not establish entropy quality, host trust or exclusive use by the guest. Reading provider metadata avoids consuming the data stream and does not measure randomness.

These guides are linked for relevant observations, not as known defects of every device in this family.

    Choose a hardware diagnostic workflow · Inspect a log excerpt in Fix Lab

    References

    Source review records a checked implementation or document, not a reproduced hardware test. Version-specific tables do not establish a minimum kernel or guaranteed operation.