[systemd-devel] [Help] Can't log in to homed user account: "No space left on device"

[Andrei Borzenkov]

23.08.2020 09:34, Andrii Zymohliad пишет:
> Hello! I've lost the ability to log in to my systemd-homed user account. I would be very grateful for any help!
> 
> If I log in as root and try to authenticate:
> 
> # homectl authenticate azymohliad
> 
> Then after typing my password I get the following output:
> 
> Operation on home azymohliad failed: Not enough disk space for home azymohliad
> 

...
> LUKS Discard: online=no offline=yes
...
> 
> My root partition is 475G, and as you can see, home file size is ~400G (I guess it was stupid to leave only 75G for root in the first place). But for some reason `btrfs fi usage /` shows that only 352G are allocated on the device before I try to authenticate (every time after boot), and full 475G after authentication attempt.


In discussion on btrfs list it was pointed out that btrfs fallocate by
design always tries to reserve space for full file size. So in this case
there are 123GB available which are not enough to reserve 400GB ...

https://lore.kernel.org/linux-btrfs/798a9077-bcbd-076c-a458-3403010ce8ac@libero.it/