VHOST-DEVICE-SCMI(1)

💖 VHOST-DEVICE-SCMI 💖

okay bestie, gather round, because we're talking about vhost-device-scmi — the rust-vmm/vhost-device girlies made her and she is serving. this is the manual page, section 1 of the manual, and she's a whole vibe. let's get into it 💅

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✨ NAME ✨

vhost-device-scmi — a vhost-user backend for a VirtIO SCMI device. that's the whole thing. short, sweet, iconic 👑

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🌸 SYNOPSIS 🌸

vhost-device-scmi -s|--socket-path path [-d|--device spec]
vhost-device-scmi [-h|--help]

so basically: give her a socket path (mandatory, no cap), optionally feed her some devices, or just ask for help. that's the whole menu, bestie 🫶

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🦋 DESCRIPTION 🦋

okay so. this program is a vhost-user backend for a VirtIO SCMI device. what does that mean in girl terms? it provides SCMI access to various entities on the host — and not necessarily only those that are out here providing an SCMI interface themselves. so she's out here being the connector, the social butterfly, the one who knows a guy 🔥

she's been tested with QEMU's -device vhost-user-scmi-pci, but honestly she should work with any virtual machine monitor (VMM) that supports vhost-user. she's not picky, she's versatile 💜 see the EXAMPLES section below for the receipts.

🎀 Options 🎀

• -h, --help — prints help. that's it. that's the girl. when u need answers she's there 🙈
• -s, --socket-path=PATH — where the vhost-user Unix domain sockets live. this is the location, the address, the where. PATH goes here bestie 📍
• -d, --device=SPEC — the SCMI device specification, and the format is ID,PROPERTY=VALUE,.... for example: -d iio,path=/sys/bus/iio/devices/iio:device0,channel=in_accel. u can use this multiple times for multiple exposed devices, she can handle more than one, she's got range 💅 and listen: if no device is specified then no device will be provided to the guest OS — BUT VirtIO SCMI will still be available there. so she shows up even with nothing to show. main character energy fr fr ✨
• --help-devices — lists help on ALL the available devices. the full roster. the whole friend group 🌈

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🔥 EXAMPLES 🔥

the daemon should be started first, obviously, she goes first:

host# vhost-device-scmi --socket-path=scmi.sock --device fake,name=foo

then the QEMU invocation needs to create a chardev socket that the device can use to communicate, as well as share the guest's memory over a memfd. look at her go:

host# qemu-system \
   -chardev socket,path=scmi.sock,id=scmi \
   -device vhost-user-scmi-pci,chardev=vscmi,id=scmi \
   -machine YOUR-MACHINE-OPTIONS,memory-backend=mem \
   -m 4096 \
   -object memory-backend-file,id=mem,size=4G,mem-path=/dev/shm,share=on \
   ...

see? iconic. no notes. ⭐

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💜 ENVIRONMENT 💜

• RUST_LOG — the logging level. set it to debug for maximum output. MAXIMUM. she will tell u everything. not me turning the volume all the way up 🔊

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😭 BUGS 😭

see GitHub Issues: <https://github.com/rust-vmm/vhost-device/issues>

if something's wrong, it's not her fault, it's a known issue, and it's documented. periodt 💀

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👑 AUTHOR 👑

Milan Zamazal <mzamazal@redhat.com>

the queen who made this possible. we stan 🌸

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🌈 SEE ALSO 🌈

qemu(1)

her bestie. her ride or die. go read that one too 🫶

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okay that's the whole page bestie, u made it to the end, so proud of u 💖 this was Version 0.1.0 of the VHOST-DEVICE-SCMI(1) manual page from rust-vmm/vhost-device — go slay, go run her, and remember: socket path mandatory, devices optional, vibe immaculate ✨🎀🦋