IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
The following operations would hang if lvm was compiled with
'enable-notify-dbus' and the client specified -1 for the timeout:
* LV snapshot merge
* VG move
* LV move
This was caused because the implementation of these three dbus methods is
different. Most of the dbus method calls are executed by gathering information
needed to fulfill it, placing that information on a thread safe queue and
returning. The results later to be returned to the client with callbacks.
With this approach we can process an arbitrary number of commands without any
of them blocking other dbus commands. However, the 3 dbus methods listed
above did not utilize this functionality because they were implemented with a
separate thread that handles the fork & exec of lvm. This is done because these
operations can be very slow to complete. However, because of this the lvm
command that we were waiting on is trying to call back into the dbus service to
notify it that something changed. Because the code was blocking the process
that handles the incoming dbus activity the lvm command blocked. We were stuck
until the client timed-out the connection, which then causes the service to
unblock and continue. If the client did not have a timeout, we would have been
hung indefinitely.
The fix is to always utilize the worker queue on all dbus methods. We need to
ensure that lvm is tested with 'enable-notify-dbus' enabled and disabled.
To help out with debug, when an exception is thrown in the dbus service we
will dump all the information we have on the last 16 commands that were
executed along with the stack strace.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
While running on F24 a number of warnings were being emitted from using the
deprecated GObject instead of GLib. Tested on python 3.4 and 3.5.
Signed-off-by: Tony Asleson <tasleson@redhat.com>
Python 3.5 in F24 was throwing the following exception:
Traceback (most recent call last):
File "/usr/lib/python3.5/site-packages/lvmdbusd/main.py", line 73, in process_request
req.run_cmd()
File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 73, in run_cmd
self.register_error(-1, st)
File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 123, in register_error
self._reg_ending(None, error_rc, error)
File "/usr/lib/python3.5/site-packages/lvmdbusd/request.py", line 115, in _reg_ending
self.cb_error(self._rc_error)
File "/usr/lib64/python3.5/site-packages/dbus/service.py", line 669, in <lambda>
keywords[error_callback] = lambda exception: _method_reply_error(connection, message, exception)
File "/usr/lib64/python3.5/site-packages/dbus/service.py", line 293, in _method_reply_error
exception))
File "/usr/lib64/python3.5/traceback.py", line 136, in format_exception_only
return list(TracebackException(etype, value, None).format_exception_only())
File "/usr/lib64/python3.5/traceback.py", line 442, in __init__
if (exc_value and exc_value.__cause__ is not None
AttributeError: 'str' object has no attribute '__cause__'
This was caused because we were calling the dbus error callback with a
string instead of an actual exception. On python 3.4 this was apparently
OK, but not with 3.5. Corrected to pass the exception to error callback.
Change tested on both python 3.4 and 3.5.
Reported-by: Vratislav Podzimek <vpodzime@redhat.com>
Signed-off-by: Tony Asleson <tasleson@redhat.com>
