[Pkg-utopia-maintainers] Bug#805449: dbus: Please reboot the system when convenient. ← ?!

[Thorsten Glaser]

Simon McVittie dixit:

>On Wed, 28 Jun 2023 at 17:24:32 +0000, Thorsten Glaser wrote:
>> Simon McVittie dixit:
>> >On a typical Debian system, restarting `dbus-daemon --system` will
>> >cause system services to stop working
>>
>> WHICH ones?
>
>I don't know what's installed on your system, so I have no way to

Yeah, but I was hoping for a method to enumerate them.

[ context ]
>> I’m pretty sure this only applies to systemd, which I don’t use.
>
>This does not only apply to systemd. avahi-daemon and bluetoothd are
>examples of services that rely on D-Bus and are older than systemd,

Indeed, but these can easily be restarted. You wrote:

>>> […] in a way that is only practical
>>> to recover from by a reboot […]

This doesn’t apply to avahi-daemon, for example.

>and elogind relies on D-Bus and is not even co-installable with systemd.

Yeah, well, no elogind here after it changed the laptop to crash¹
on lid close. I threw that out very quickly…

① it tried to suspend, but I don’t have suspend-to-disc set up

>If you use `sudo ss --unix -p` instead of netstat, you can correlate
[…]

Oh, that seems better. I haven’t used the ss tool yet.

$ sudo ss --unix -p | fgrep dbus
u_str ESTAB 0      0      /run/dbus/system_bus_socket 1356473            * 1355554 users:(("dbus-daemon",pid=1497,fd=9))
u_str ESTAB 0      0             /tmp/dbus-HWIk9QtjqW 1370793            * 1359638 users:(("dbus-daemon",pid=9974,fd=15))
u_str ESTAB 0      0                                * 15526              * 15527   users:(("dbus-daemon",pid=1497,fd=7))
u_str ESTAB 0      0                                * 15527              * 15526   users:(("dbus-daemon",pid=1497,fd=8))
u_str ESTAB 0      0                                * 1370736            * 1359493 users:(("dbus-launch",pid=9973,fd=3))
u_str ESTAB 0      0                                * 1359499            * 1359500 users:(("dbus-launch",pid=9973,fd=4))
u_str ESTAB 0      0                                * 1359498            * 1359497 users:(("dbus-daemon",pid=9974,fd=7))
u_str ESTAB 0      0             /tmp/dbus-HWIk9QtjqW 1370769            * 1359608 users:(("dbus-daemon",pid=9974,fd=11))
u_str ESTAB 0      0                                * 1359497            * 1359498 users:(("dbus-daemon",pid=9974,fd=6))
u_str ESTAB 0      0             /tmp/dbus-HWIk9QtjqW 1370774            * 1359625 users:(("dbus-daemon",pid=9974,fd=14))
u_str ESTAB 0      0             /tmp/dbus-HWIk9QtjqW 1370770            * 1359618 users:(("dbus-daemon",pid=9974,fd=12))
u_str ESTAB 0      0      /run/dbus/system_bus_socket 1359632            * 1359631 users:(("dbus-daemon",pid=1497,fd=11))
$ sudo ss --unix -p | fgrep 1355554
u_str ESTAB 0      0      /run/dbus/system_bus_socket 1356473            * 1355554 users:(("dbus-daemon",pid=1497,fd=9))
u_str ESTAB 0      0                                * 1355554            * 1356473 users:(("Xorg",pid=3548,fd=11))
$ sudo ss --unix -p | fgrep 1359631
u_str ESTAB 0      0                                * 1359631            * 1359632 users:(("xdg-desktop-por",pid=9999,fd=7))
u_str ESTAB 0      0      /run/dbus/system_bus_socket 1359632            * 1359631 users:(("dbus-daemon",pid=1497,fd=11))
$ ps ax -q 3548,9999
  PID TTY      STAT   TIME COMMAND
 3548 tty2     Rl     2:09 /usr/lib/xorg/Xorg -retro -nolisten tcp -dpi 106 :0 vt2 -keeptty -auth /tmp/serverauth
 9999 ?        Sl     0:00 /usr/libexec/xdg-desktop-portal

The output is wider than my laptop screen, despite being cut off,
but I can now see that, on this machine, it’s apparently the X11
server (why?) and xdg-desktop-portal (understandable, but TTBOMK
that gets (re‑?)started automatically anyway, it’s for Firefox).

But this is basically what I was looking for, yes.

>can be avoided by micro-optimizing how you deal with dbus updates. The
>kernel gets at least an order of magnitude more security updates than

Yeah, depends, I occasionally have a VM host with long-running tasks
on the VMs. I was able to reboot it anyway today but was interested in
how this can be generically decided.

Feel free to extract this discussion into README.Debian of dbus.

Thanks,
//mirabilos
-- 
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If you don't believe in God, just consider God as Nature if you won't deny
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