Hylafax on FreeBSD 10 and 100% CPU

[Konstantin Belousov]

On Wed, Jul 02, 2014 at 10:35:16AM +0100, Daren wrote:
> Hi
> 
> I've tried installing Hylafax from ports on fresh FreeBSD 10.  We
> previously had it running on an 8.2 system without issue.
> 
> After starting faxgetty creeps up to and stays on 100% cpu.  I did find
> a previous PR for this
> (https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=166071) which has the
> status of resolved fixed although people have requested it be re-opened
> as the problem is still occurring for them as well.
> 
> I can add another comment to this if it helps get it noticed again, but
> my knowledge with C etc is non-existent to be able to help with it,
> although searching has come up with a similar/same issue on dragonflybsd
> (http://bugs.dragonflybsd.org/issues/2028)
> 
> Does anyone know if this is being looked at?
> 

I once looked at the source code of the program, and the ktrace reports
in the mentioned PR 166071 are consistent with what I remember I saw in
code, as well as what was discussed at that time.

If you look at the kdump, you note the series of read(2) syscalls on the
same FIFO, which return 0, the indicator of the EOF.  AFAIR, the Hylafax
code does  not check for the EOF condition and just spins trying to
read more data.  Select(2) returns the fd for EOF'ed FIFO ready, because
the read(2) indeed does not block at EOF.

My decision at that time was that the issue is the program bug.
I do not use the program, and cannot set it up locally to even try
coding the fix.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <http://lists.freebsd.org/pipermail/freebsd-ports/attachments/20140703/f2dc22b7/attachment.sig>