Andrey,

I think something is wrong with your setup.

On Wed, Jun 28, 2023 at 02:59:41PM +0700, А. Сорокин via Dng wrote:
> I have installed Daedalus-preview, and have noticed, that it does not
> let me open second X-session (from another TTY), when there is already
> one X-session is opened (from one TTY). Before firing a bug, i wanted
> to counsel here -- may i have missed something, and now it is intended
> system behaviour.
>
> In the X lof file i get the following corresponding errors:
>
> [ 5304.581] (II) seatd_libseat init
> [ 5304.582] (EE) [libseat/backend/seatd.c:308] Could not poll connection: Broken pipe
> [ 5304.582] (II) [libseat/libseat.c:76] Backend 'seatd' failed to open seat, skipping

If seatd is installed and running, this is unexpected.

I have

$ dpkg -l seatd
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend

|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name           Version      Architecture Description
+++-==============-============-============-================================================
ii  seatd          0.7.0-6      amd64        minimal user, seat and session management daemon
$ ps -lfC seatd
F S UID        PID  PPID  C PRI  NI ADDR SZ WCHAN  STIME TTY          TIME CMD
4 S root      1500     1  0  80   0 -   623 -      Jun18 ?        00:00:00 /usr/sbin/seatd -g video
$ ls -l /run/seatd.*
-rw-r--r-- 1 root root  5 Jun 18 10:40 /run/seatd.pid
srwxrwx--- 1 root video 0 Jun 18 10:40 /run/seatd.sock

If yours doesn't look like that reinstall/configure seatd.

> [ 5304.612] (II)[libseat/libseat.c:73] Seat opened with backend 'logind' [ 5304.612]

But you also have elogind installed and running. Do you need/want that?

I suggest you avoid using both seatd and elogind whilst debugging. You can either

- uninstall whichever you don't want

- Use the LIBSEAT_BACKEND environment variable to limit. For example

      LIBSEAT_BACKEND=logind startx

Always use the same backend for both startx sessions.

Mark

> (II) seatd_libseat enable [ 5304.612] (II) seatd_libseat handled 1
> events [ 5304.612] (II) seatd_libseat handled 1 events
> [ 5304.713] (II) seatd_libseat client activated
> [ 5304.713] (II) xfree86: Adding drm device (/dev/dri/card0)
> [ 5304.713] (II) Platform probe for
> /sys/devices/pci0000:00/0000:00:02.1/0000:01:00.0/drm/card0 [
> 5304.713] (II) seatd_libseat try open graphics /dev/dri/card0 [
> 5304.714] (EE) [libseat/backend/logind.c:137] Could not take device:
> Device or resource busy [ 5304.714] (EE) seatd_libseat open graphics
> /dev/dri/card0 (-1) failed: -11

Do you have a display manager installed as well (slim, lightdm, sddm, gdm...)?
If so, stop it and try again.

Mark