[PATCH] poll() hang with X apps

[Robert Watson]

On Sun, 5 Sep 2004, Maxim Maximov wrote:

> Doug White wrote:
> > Attaching to an earlier message here...
> > 
> > rwatson and I may have a solution to the poll() hangs you have been
> > experiencing. Try downloading and applying this patch:
> > 
> > http://www.watson.org/~robert/freebsd/netperf/20040905-sopoll.diff
> > 
> > This seems to stop the hangs on my test system (2x600MHz P3 with XFree
> > 4.3). I'll test it with its partner, a RELENG_5 box with either Xorg or
> > XFree86 4.4.  Please test it and get back to us if its working for you.
> 
> Oh my! I'm recompiling my kernel already! 
> 
> I began to think that this problem was abandoned, but there were work
> going on! Thank you and Robert! 

Yeah, I had a good idea about what the problem might be, but I couldn't
reproduce it here.  Happily, Doug could and was willing to spend a lot of
time with the debugger to track stuff down.  Turns out it may have been a
potential race I tagged when I was originally reviewing that element of
socket locking, but hadn't yet had a chance to revisit.  If the patch
fixes it, wonderful!  If not, there are one or two other things in the
polling/select code that could use review.  Assuming this patch does fix
the problem for you (it did for Doug), I'll get it merged into HEAD
tomorrow, and RELENG_5 a few days later.

Thanks for your bug report, and we'll see how it goes :-).

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Principal Research Scientist, McAfee Research