Bug 738355

Summary: [vdsm] [guestIF] UnboundLocalError: local variable 'line' referenced before assignment
Product: Red Hat Enterprise Linux 6 Reporter: David Naori <dnaori>
Component: vdsmAssignee: Gal Hammer <ghammer>
Status: CLOSED DUPLICATE QA Contact: David Naori <dnaori>
Severity: low Docs Contact:
Priority: unspecified    
Version: 6.1CC: abaron, bazulay, danken, dnaori, hateya, iheim, mgoldboi, ykaul
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-09-15 11:00:56 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Attachments:
Description Flags
vdsm log none

Description David Naori 2011-09-14 15:34:17 UTC
Created attachment 523183 [details]
vdsm log

Description of problem:

Thread-825::ERROR::2011-09-14 17:52:02,018::guestIF::268::vm.Vm::(run) vmId=`ff1ef43c-bf3d-4231-8545-26731306a048`::Unexpected exception: Traceback (most recent call last):
  File "/usr/share/vdsm/guestIF.py", line 265, in run
    self.log.exception("Run exception: %s", line)
UnboundLocalError: local variable 'line' referenced before assignment

            while not self._stopped:
                try:
                    line = self._readLine()
                    # line is always None after stop() is called and the
                    # socket is closed.
                    if line:
                        (message, args) = self._parseLine(line)
                        self._agentTimestamp = time.time()
                        self._handleMessage(message, args)
                except:
                    self.log.exception("Run exception: %s", line)


should set line to None before the read

Version-Release number of selected component (if applicable):
vdsm-4.9-98.el6.x86_64

How reproducible:
happened in migration destenation

Actual results:


Expected results:


Additional info:

Comment 2 Dan Kenigsberg 2011-09-14 18:28:42 UTC
BTW David, this bug was introduced in vdsm-4.9-99-7-ga5f8785 (vdsm-4.9-100).

Any word on how to reproduce it, and the functional effect?

Thanks for the suggested fix, I've posted it under your name at

http://gerrit.usersys.redhat.com/936

Comment 3 David Naori 2011-09-14 21:08:40 UTC
(In reply to comment #2)
> BTW David, this bug was introduced in vdsm-4.9-99-7-ga5f8785 (vdsm-4.9-100).
> 
> Any word on how to reproduce it, and the functional effect?
> 
> Thanks for the suggested fix, I've posted it under your name at
> 
> http://gerrit.usersys.redhat.com/936

i don't know if there is any functional effects, and i don't know exactly how to reproduce it, i just saw it in the log after some concurrent migrations -
since the fix is simple i didn't find it significant to investigate the cause.

i can try to reproduce it anytime if needed.

Comment 5 Dan Kenigsberg 2011-09-15 11:00:56 UTC
If not fixed, vdsm may stop waiting for guest messages after migration (which is bad). This is a failure of the first implementation of the fix for bug 736422, and should be verified as a part of it. No need to chase more flags.

*** This bug has been marked as a duplicate of bug 736422 ***