The hardware-observe interface

The hardware-observe interface allows for getting hardware information from the system.

hardware-observe grants read-only access to many files and directories, primarily in /sys and /proc. Additionally, it provides access to many utility files and binaries such as lspci, lsusb, and hwinfo.

hardware-observe is a more general and broad interface. If more specific hardware access is required, such as for GPIO or I2C devices, See the gpio and i2c interfaces.

Tip

See Interface management and Supported interfaces for further details on how interfaces are used.

Developer details

Auto-connect: no

Path access

hardware-observe grants read access to the following paths:

  • For tools like hwinfo --short to get hardware information:
    /proc/ioports
    /proc/dma
    /proc/tty/driver/{,*}
    /proc/sys/dev/cdrom/info

  • For tools like lshw -quiet to get hardware information:
    /proc/devices
    /proc/ide/{,**}
    /proc/scsi/{,**}
    /proc/device-tree/{,**}
    /sys/kernel/debug/usb/devices
    /proc/sys/abi/{,*}

  • For tools like lspci -A linux-sysfs to get information on files in /sys:
    /sys/{block,bus,class,devices,firmware}/{,**}

  • For tools like lspci -A linux-proc to get information on /proc:
    /bus/pci/{,**} /{,usr/}lib/modprobe.d/{,*}

  • For tools like lspci -k to get information on loaded modules:
    Examples: /etc/modprobe.d/{,*},

  • For tools like lsusb to get USB information:
    /var/lib/usbutils/usb.ids
    /dev/
    /dev/bus/usb/{,**/}
    /etc/udev/udev.conf
    Note: lsusb and its database have to be shipped in the snap if not on classic

  • For tools like sensors to get sensor information:
    /etc/sensors3.conf
    /etc/sensors.d/{,*}

  • For tools like udevadm to get device information:
    /run/udev/data/**

  • For hugepage and transparent_hugepage statuses (but not the pages themselves):
    /sys/kernel/mm/{hugepages,transparent_hugepage}/{,**}

  • For information on available input devices:
    /proc/bus/input/devices

  • For power information:
    /sys/power/{,**}
    /run/udev/data/+power_supply:*

  • For interrupts:
    /proc/interrupts

  • For loaded kernel module information:
    /proc/modules

  • For VM information:
    /proc/cpuinfo
    /proc/sysinfo
    /proc/xen/capabilities
    /proc/1/sched
    /sys/hypervisor/properties/features
    /sys/hypervisor/type

  • For container information:
    /run/systemd/container

Binary access

hardware-observe grants executable access to the following binaries:

  • For tools provided by util-linux:
    /{,usr/}bin/lsblk
    /{,usr/}bin/lscpu
    /{,usr/}bin/lsmem

  • For tools like lsusb:
    /{,usr/}bin/lsusb

  • For tools like systemd-detect-virt:
    /{,usr/}bin/systemd-detect-virt

Capability access

hardware-observe grants the following capabilities:

  • For tools like lscpu and lspci -A to inspect specific PCI access methods:
    capability sys_rawio
    capability sys_admin

Socket access

hardware-observe grants the following socket access:

  • For udevadm to read netlink:
    network netlink raw

The test code for the interface is in the snapd repository: https://github.com/canonical/snapd/blob/master/interfaces/builtin/hardware_observe_test.go

The source code for the interface is in the snapd repository: https://github.com/canonical/snapd/blob/master/interfaces/builtin/hardware_observe.go