freebsd stable - Jun 2009 - HEADSUP: libpthread compat for 5.x and 6.x binaries

One of the changes in FreeBSD 8.0 is the removal of support for the KSE 
threading library and its associated system calls.  What this means in 
practice is that if one uses a KSE-based libpthread from 5.x or 6.x in a 
chroot or jail on an 8.0 system, the binaries will fail with SIGSYS.  For 
most (possibly all) binaries, this can be worked around by using libthr 
instead libpthread.  FreeBSD 7.0 and later ship with libthr as the threading 
library installed as libpthread.

What I would like to find out is if there are any 5.x or 6.x binaries that use 
libpthread that do not run well with libthr.  You can test this by using a 
libmap.conf(5) file to remap libpthread to libthr.  For 5.x binaries you will 
want to remap libpthread.so.1 to libthr.so.1.  For 6.x binaries you will want 
to remap libpthread.so.2 to libthr.so.2.  This can be accomplished using 
an /etc/libmap.conf file that contains:

<quote file="/etc/libmap.conf">
# Remap 5.x and 6.x libpthread to libthr
libpthread.so.1		libthr.so.1
libpthread.so.2		libthr.so.2
</quote>

To my knowledge, most binaries should work fine in this configuration.  One 
binary that I am aware of that does have problems is the 'arcconf'
binary
from ports.  However, for this particular case there is a binary for 7.x 
available for use on 8.0 systems.

-- 
John Baldwin

John Baldwin wrote:
> What I would like to find out is if there are any 5.x or 6.x binaries that
use
> libpthread that do not run well with libthr.  You can test this by using a 
> libmap.conf(5) file to remap libpthread to libthr.  For 5.x binaries you
will
> want to remap libpthread.so.1 to libthr.so.1.  For 6.x binaries you will
want
> to remap libpthread.so.2 to libthr.so.2.  This can be accomplished using 
> an /etc/libmap.conf file that contains:
I'm running about a hundred jails with a libmap.conf file like that. In
order to run 32-bit 6.x jails on FreeBSD 7.2 64-bit...

The only time I've seen a problem, is when a threaded application binary
is compiled statically. Apparently mysql is built statically sometimes.
Obviously in these cases libmap.conf can't kick in.

Cheers,

Stef Walter