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

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

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