Re: kern/46402: LWPs created after exit_lwp() is called can hang the process....

[Greg Oster <oster%cs.usask.ca@localhost>]

The following reply was made to PR kern/46402; it has been noted by GNATS.

From: Greg Oster <oster%cs.usask.ca@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: bouyer%antioche.eu.org@localhost, kern-bug-people%netbsd.org@localhost,
 gnats-admin%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost, 
oster%netbsd.org@localhost
Subject: Re: kern/46402: LWPs created after exit_lwp() is called can hang
 the process....
Date: Thu, 3 May 2012 10:22:21 -0600

 On Thu,  3 May 2012 15:00:07 +0000 (UTC)
 Manuel Bouyer <bouyer%antioche.eu.org@localhost> wrote:
 
 > The following reply was made to PR kern/46402; it has been noted by
 > GNATS.
 > 
 > From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
 > To: gnats-bugs%NetBSD.org@localhost
 > Cc: kern-bug-people%NetBSD.org@localhost, gnats-admin%NetBSD.org@localhost,
 > netbsd-bugs%NetBSD.org@localhost Subject: Re: kern/46402: LWPs created after
 > exit_lwp() is called can hang the process....
 > Date: Thu, 3 May 2012 16:57:09 +0200
 > 
 >  On Wed, May 02, 2012 at 09:30:00PM +0000, oster%NetBSD.org@localhost wrote:
 >  > While running an extended series of aft-tests I noticed that the
 >  > test were occasionally hanging.  It turns out they were hanging at
 >  > the same place, and that the test is repeatable.  Running the
 >  > following:
 >  > 
 >  >  cd /usr/tests/lib/libpthread
 >  >  foreach i (`jot 10000`)
 >  >  ./t_cond cond_timedwait_race 
 >  >  echo $i
 >  >  end
 >  > 
 >  
 >  Sounds familiar: kern/46168
 
 yes!  That's exactly the same bug....  I ran with a patch very, very
 similar to the one you had in 46168, but I'd end up with a very hard
 kernel hang after some time... (couldn't break into ddb as normal,
 even).
 
 >  Andrew Doran had some improvements to the patch I proposed here, but
 > it seems he forgot to send me an updated patch (this was a month ago).
 >  I guess we should get the patch in kern/46168 commited then ...
 
 I don't think it's sufficient, unfortunately... there's still something
 else missing.. :(  
 
 Later...
 
 Greg Oster