Bug#760142: systemd: Assertions from systemd-logind on powerpc during login, with continuing loop

[Simon McVittie]

On Wed, 19 Nov 2014 at 21:29:33 +0100, Andreas Messer wrote:
> I'm observing the same behavior on an x86_64 wheezy system running my
> HTPC setup after updating the system some weeks ago.

Andreas, I think your bug is #769069, which is a recent regression:
your system is presumably much less slow than Chris's.

> The problem disappeared after downgrade to dbus 1.6.8-1+deb7u1

You don't want that version, it has a known buffer overrun.

Please try upgrading to 1.6.8-1+deb7u4 again, then creating
/etc/dbus-1/system-local.conf containing this:

    <busconfig>
      <limit name="auth_timeout">30000</limit>
    </busconfig>

That effectively reverts the problematic part of the changes from 1.6.8-1+deb7u4.
Please let me know whether that makes it reliable for you.

Please delete that file when you have upgraded to a version where #769069
is fixed. I'm probably going to revert that change upstream and in Debian,
it's causing problems for several people.

On Wed, 03 Sep 2014 at 16:55:03 +1200, Chris Tillman wrote:
> Yes, it is installed on a USB hard disk. I mentioned it in the first
> bug report I filed [...] And yes, I think the timing issue could be
> getting exacerbated because of the slowness of USB.

Chris, with hindsight, your symptoms look a lot like #769069; but they can't be a
regression in that version of dbus, because your bug report is older
than the change that has caused the regression for others.

It would be great if you could install the test package described in
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=769069#85
which will log a message containing "Connection has not authenticated soon enough"
when authentication takes too long - I suspect that's the failure case that
you're reaching.

After doing that, you might be able to make this work on your system by creating
/etc/dbus-1/system-local.conf containing this:

    <busconfig>
      <limit name="auth_timeout">90000</limit>
      <limit name="service_start_timeout">90000</limit>
    </busconfig>

or perhaps even longer. They are in milliseconds (thousandths). The default for
auth_timeout is currently 5000, but it was 30000 when you opened your bug report,
and I'm probably going to revert to that; the default for service_start_timeout
is 25000.

Sorry, but I am reluctant to increase the defaults enough for your system, because
the longer auth_timeout is, the easier it is for a local user to carry out a
denial of service attack; and the longer service_start_timeout is, the longer
you have to wait to get an error if something is misconfigured.

Regards,
    S