[systemd-devel] No device unit created

[Richard Maw]

On Mon, Sep 07, 2015 at 03:42:11PM +0200, jean-philippe francois wrote:
> Hi,
> 
> I have a problem I don't know how to debug.
> The documentation for device units says :
> 
> systemd will dynamically create device units for all kernel devices
> that are marked with the "systemd" udev tag
> 
> Howevever, while the device I am waiting for are given the systemd
> tag, it seems no device unit is ever created.
> This is on an embedded machine,

First thing to check here is your kernel version and whether you have
CONFIG_FHANDLE enabled in your kernel.

Unfortunately FHANDLE is not enabled by default and systemd/udev require it.

New enough kernels and systemd versions have fallback code when the system
calls provided by FHANDLE are not available, but for a while there was a period
where the common kernel configurations weren't sufficient for running systemd.