[apparmor] [PATCH] 0001-fix-aa-sandbox-race.patch

[Jamie Strandboge]

On 02/15/2013 11:48 AM, Seth Arnold wrote:
> On Fri, Feb 15, 2013 at 11:10:24AM -0600, Jamie Strandboge wrote:
>> +        for i in range(self.timeout): # Up to self.timeout seconds to start
>>              rc, out = cmd(['xpra', 'list'])
>> +
>> +            if 'DEAD session at %s' % self.display in out:
>> +                error("xpra session at '%s' died" % self.display, do_exit=False)
>> +                break
>> +
>> +            search = 'LIVE session at %s' % self.display
>> +            if search in out:
>>                  started = True
>>                  break
>>              time.sleep(1)
>> +            debug("Could not find '%s' in:\n" % search)
>> +            debug(out)
> 
> Could this sleep be changed to .5 seconds without too much overhead? Or,
> how long does it usually take?
> 

This could be reduced to 0.5 seconds-- it isn't normally hit.

>>          if not started:
>>              sys.stdout.flush()
>> @@ -638,6 +662,17 @@
>>  
>>          self.pids.append(listener_attach)
>>  
>> +        # Make sure that a client has attached
>> +        for i in range(self.timeout): # up to self.timeout seconds to attach
>> +            time.sleep(1)
>> +            rc, out = cmd (['xpra', 'info', self.display])
>> +            search = 'clients=1'
>> +            if search in out:
>> +                debug("Client successfully attached!")
>> +                break
>> +            debug("Could not find '%s' in:\n" % search)
>> +            debug(out)
>> +
>>          msg("TODO: filter '~/.xpra/run-xpra'")
> 
> How about this sleep, too? Could the sleep be profitably moved after the
> check, to optimistically assume that it might succeed immediately?
> 
> Thanks Jamie
> 

In my experience, you need the one second here which is why I put it first.

Also, I want to mention that these patches improve things, but don't
make aa-sandbox with xpra bullet-proof. Xpra is kinda finicky and isn't
easily drivable so there are other bugs in there, but we can fix them as
we find them.

-- 
Jamie Strandboge                 http://www.ubuntu.com/

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