[linux-lvm] [PATCH 1/1] pvscan: wait for udevd

[Martin Wilck]

On Fri, 2021-02-19 at 23:47 +0100, Zdenek Kabelac wrote:
> 
> Right time is when switch is finished and we have rootfs with /usr
> available - should be ensured by  lvm2-monitor.service and it
> dependencies.

While we're at it - I'm wondering why dmeventd is started so early. dm-
event.service on recent installments has only "Requires=dm-
event.socket", so it'll be started almost immediately after switching
root. In particular, it doesn't wait for any sort of device
initialization or udev initialization.

I've gone through the various tasks that dmeventd is responsible for,
and I couldn't see anything that'd be strictly necessary during early
boot. I may be overlooking something of course. Couldn't the monitoring
be delayed to after local-fs.target, for example?

(This is also related to our previous discussion about
external_device_info_source=udev; we found that dmeventd was one of the
primary sources of strange errors with that setting).

Regards
Martin