[Devel] [Q] migrating inotify assigned on ploop device

[Cyrill Gorcunov]

Hi guys, today I've been investigating a problem of container's migration
with inotify assigned on /dev/ploop10308p1 device. The main problem is that
the mark is set to devtmpfs where device ID and inode number is not persistent
by default so to workaraound such problem we keep a real "path" to the watchee
inside image which eventually get used on restore procedure, but because of
ploop nature at the moment of restore the former /dev/ploop10308p1 is transformed
into the new device /dev/ploop46339p1 so as expected the restore procedure fails.

Been talking to Pavel and the proper general solutions is "device namespace" which
require significant kernel update/rework so I don't consider it as a solution
which could be implemented in a day or two. Instead another option might be
to use CRIT tool and decode|encode device path on the fly via libvzctl or
p.haul project.

Any other ideas comments?