flowtable_cleaner/flowtable_flush livelock

[Bjoern A. Zeeb]

On Sat, 20 Nov 2010, Mikolaj Golub wrote:

Hey,

> On Sat, 20 Nov 2010 17:03:13 +0000 (UTC) Bjoern A. Zeeb wrote:
>
> BAZ> I think net@ would have been a better initial place but since this
> BAZ> seems to be a problem when interacting with VIMAGE
> BAZ> freebsd-virtualization might be better.
>
> BAZ> What you could try is:
> BAZ> http://people.freebsd.org/~bz/20100216-10-ft-cv.diff
>
> Ah, I have recalled I had already saw this patch but did not understand what
> the problem was that it fixed, thus did not associated it with my case
> (actually, I thought you had committed all these patches to the tree long time
> ago and I was running the kernel with them already :-).
>
> BTW, the patch needs updating: in the current flow_full() wakes up flowcleaner
> too, and flowcleaner sleeps for flowclean_freq instead of 10*hz (see the
> attached patch).

For sure it does; as you can see form the date in the file name, that
patch was from the beginning of the year.

> With the patch I can't reproduce the lock. Only the crash I mentioned in my
> first letter is observed:

Hmm, I guess I should get the updated version comitted then.


How do you reproduce the crash?  Is it just another ifioctl race as
from kern/146250?

/bz

-- 
Bjoern A. Zeeb                              Welcome a new stage of life.
         <ks> Going to jail sucks -- <bz> All my daemons like it!
   http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/jails.html