hp-systray fails after suspend and resume

[Johannes Meixner]

I got probably two bugs (reported by a colleague):

1)
hp-systray runs busy-loop after suspend and resume
for HPLIP 2.8.4 in openSUSE 11.0, see
https://bugzilla.novell.com/show_bug.cgi?id=433789

The reason here is that an an empty read is ignored
(an empty read should be taken as EOF).

2)
hp-systray fails after suspend and resume
for HPLIP 2.8.7 in openSUSE 11.1, see
https://bugzilla.novell.com/show_bug.cgi?id=433789#c4
It fails with
--------------------------------------------
ERROR:dbus.connection:Exception in handler for D-Bus signal:
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/dbus/connection.py", line 214, in
maybe_handle_message
    self._handler(*args, **kwargs)
  File "/usr/bin/hp-toolbox", line 96, in handle_session_signal
    sys.exit(1)
SystemExit: 1
--------------------------------------------
and in dmesg there is
--------------------------------------------
python[10473]: segfault at 4 ip b67fe4bb sp bfd57900
error 6 in libdbus-1.so.3.4.0[b67d6000+40000]
--------------------------------------------

Some comments:

I noticed already
https://bugs.launchpad.net/ubuntu/+source/hplip/+bug/303753
but I think this one is different.

All three cases seem to have a root cause outside of HPLIP
(a no longer accessible file descriptor, something broken in dbus,
something broken in the lower-level USB system).

Nevertheless it seems also that HPLIP is not robust against
such kind of errors but seems to blindly trust that all goes on well.

Of course HPLIP cannot implement fixes for whatever breaking
stuff after a suspend and resume but HPLIP should be robust
against whatever errors which can happen all the time during
runtime (e.g. when file I/O suddenly fails, when communication
via dbus suddenly fails, when communication with a USB device
suddenly fails, whatever else...) and exit at least with a nice
error message popup so that the user is at least informed.

[Linus Araque (linus-araque)]

I'm unable to reproduce this bug. My test setup is as follows:

Test PC - Compaq Evo N410c
Distro - SuSE 11.0 32bit
HPLIP - 3.9.1.9-internal
Test Unit - OfficeJet J6400
Connection - LAN

I'm suspending the system via the "Hibernate" command in the shutdown menu, then bringing the system back up by hitting the power button and logging in. I made sure hp-systray was running before I suspended the system, then made sure the systray was still responding after bringing the system back up. There were no errors in the terminal throughout the suspend cycle.

Can you try to reproduce using a newer build? 2.8.12 is available at hplipopensource.com

[Johannes Meixner (jsmeix)]

Good to see that it doesn't fail in any case!

Currently I don't have the time to work on newer HPLIP versions
for openSUSE but in March/April I will provide as usual the newest
HPLIP version via our openSUSE build service for openSUSE 11.1
so that my colleague who reported the issue could test it.

[dwelch91 (dwelch91)]

I would still like to put some defensive code in to handle this in case its
not really fixed... but, since we can't reproduce this issue, I'm certain
where and what to do. Can anyone help with this?

On Thu, Jan 22, 2009 at 2:20 AM, Johannes Meixner <email address hidden> wrote:

> Good to see that it doesn't fail in any case!
>
> Currently I don't have the time to work on newer HPLIP versions
> for openSUSE but in March/April I will provide as usual the newest
> HPLIP version via our openSUSE build service for openSUSE 11.1
> so that my colleague who reported the issue could test it.
>
> --
> hp-systray fails after suspend and resume
> https://bugs.launchpad.net/bugs/319231
> You received this bug notification because you are a member of HP Linux
> Imaging and Printing, which is subscribed to HPLIP.
>