freebsd stable - Jul 2009 - process stuck in "umtxn"

Hello!

I noticed, that my build of KDE4 ports got suspiciously quiet...
Pressing Ctrl-T shows:

    load: 0.01  cmd: automoc4 78507 [umtxn] 0.00u 0.00s 0% 3552k

According to gdb, the process' stack is:

    #0  0x0000000800d9620a in __error () from /lib/libthr.so.3
    #1  0x0000000800d95f0c in __error () from /lib/libthr.so.3
    #2  0x0000000800d911eb in pthread_mutex_getyieldloops_np () from
    /lib/libthr.so.3
    #3  0x0000000800f0941b in _malloc_postfork () from /lib/libc.so.7
    #4  0x0000000800d93c60 in fork () from /lib/libthr.so.3
    #5  0x0000000800778e4a in QProcessPrivate::startProcess () from
    /opt/lib/qt4/libQtCore.so.4
    #6  0x000000080073f2c6 in QProcess::start () from
    /opt/lib/qt4/libQtCore.so.4
    ....

My system is 7.2-PRERELEASE/amd64 from April 9th. Please, advise.
Thanks! Yours,

    -mi

In the last episode (Jul 09), Mikhail T. said:
> I noticed, that my build of KDE4 ports got suspiciously quiet...  Pressing
> Ctrl-T shows:
> 
>     load: 0.01  cmd: automoc4 78507 [umtxn] 0.00u 0.00s 0% 3552k
> 
> According to gdb, the process' stack is:
> 
>     #0  0x0000000800d9620a in __error () from /lib/libthr.so.3
>     #1  0x0000000800d95f0c in __error () from /lib/libthr.so.3
>     #2  0x0000000800d911eb in pthread_mutex_getyieldloops_np () from
/lib/libthr.so.3
>     #3  0x0000000800f0941b in _malloc_postfork () from /lib/libc.so.7
>     #4  0x0000000800d93c60 in fork () from /lib/libthr.so.3
>     #5  0x0000000800778e4a in QProcessPrivate::startProcess () from
/opt/lib/qt4/libQtCore.so.4
>     #6  0x000000080073f2c6 in QProcess::start () from
/opt/lib/qt4/libQtCore.so.4
>     ....
> 
> My system is 7.2-PRERELEASE/amd64 from April 9th. Please, advise.
> Thanks! Yours,
That could be due to the following bug, fixed after 7.2 was released. 
Appliying the patch and rebuilding libc should be all you need to fix it:

http://security.freebsd.org/advisories/FreeBSD-EN-09:04.fork.asc

-- 
	Dan Nelson
	dnelson@allantgroup.com