diff --git a/docs/system/device-emulation.rst b/docs/system/device-emulation.rst index 7afcfd8064..19944f526c 100644 --- a/docs/system/device-emulation.rst +++ b/docs/system/device-emulation.rst @@ -88,3 +88,4 @@ Emulated Devices devices/usb.rst devices/vhost-user.rst devices/virtio-pmem.rst + devices/vhost-user-rng.rst diff --git a/docs/system/devices/vhost-user-rng.rst b/docs/system/devices/vhost-user-rng.rst new file mode 100644 index 0000000000..a145d4105c --- /dev/null +++ b/docs/system/devices/vhost-user-rng.rst @@ -0,0 +1,39 @@ +QEMU vhost-user-rng - RNG emulation +=================================== + +Background +---------- + +What follows builds on the material presented in vhost-user.rst - it should +be reviewed before moving forward with the content in this file. + +Description +----------- + +The vhost-user-rng device implementation was designed to work with a random +number generator daemon such as the one found in the vhost-device crate of +the rust-vmm project available on github [1]. + +[1]. https://github.com/rust-vmm/vhost-device + +Examples +-------- + +The daemon should be started first: + +:: + + host# vhost-device-rng --socket-path=rng.sock -c 1 -m 512 -p 1000 + +The QEMU invocation needs to create a chardev socket the device can +use to communicate as well as share the guests memory over a memfd. + +:: + + host# qemu-system \ + -chardev socket,path=$(PATH)/rng.sock,id=rng0 \ + -device vhost-user-rng-pci,chardev=rng0 \ + -m 4096 \ + -object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on \ + -numa node,memdev=mem \ + ...