[systemd-devel] What's mounting this partition?

[Paul D. DeRocco]

I have a Yocto-built x86 system, running off a USB flash drive that has
two partitions on it. /dev/sda1 is a small FAT file system that I use for
persistent data storage, and isn't bootable. /dev/sda2 is the root file
system, which boots via Syslinux. I use a mount unit to mount /dev/sda1 on
/media/chroma. However, it finds that /dev/sda1 is already mounted on
/media/sda1. It goes ahead and mounts it anyway, with a warning, but my
mount options (noatime,tz=UTC) are ignored.

I tried putting the /media/chroma mount in fstab. Now it fails entirely,
perhaps because systemd-fstab-generator won't create a mount unit for
something that's already mounted somewhere else.

But what I can't figure out is what the heck is mounting /dev/sda1 on
/media/sda1 in the first place. None of the generators in
/lib/systemd/system-generators seem to be to blame, according to their
docs. How do I make it not do that, so that I can mount it with my own
options, either in fstab or with an explicit mount unit? The version of
the system I did a couple of years ago, with an earlier Yocto, an earlier
systemd, and an earlier kernel, didn't have this behavior.

And while we're at it, is there a way to control what mount options it
uses for the root? I'd like to use noatime, so that it doesn't abuse my
flash drive needlessly.

-- 

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco at ix.netcom.com