[mapserver-dev] Fwd: mapserver deadlock on signal

[Stephan Holl]

Hello Devs,

Lauri <lauri.nomme at gmail.com>, [20111108 - 15:35:51]

> Hi
> 
> There is a bug in how mapserver handles USR1 and TERM signals when
> used in fastcgi mode.
> msCleanupOnSignal calls msCleanup, which calls gdFontCacheShutdown
> which tries to acquire a mutex that can already be locked, deadlocking
> the process.

We are forcing this issue withlibapache2-mod-fcgid  and
MapServer 6.0.1. Is there an issue for this patch in trac or is this
already solved in trunk?

Best

	Stephan


> A sample stack trace showing the symptoms:
> Process 12533 attached - interrupt to quit
> futex(0x7ffdcb1b7d80, FUTEX_WAIT_PRIVATE, 2, NULL
> 
> (gdb) bt
> #0  0x00007fdf9ec99be4 in __lll_lock_wait () from /lib/libpthread.so.0
> #1  0x00007fdf9ec950e9 in _L_lock_953 () from /lib/libpthread.so.0
> #2  0x00007fdf9ec94f0b in pthread_mutex_lock ()
> from /lib/libpthread.so.0 #3  0x00007fdfa19edf1a in
> gdFontCacheShutdown () from /usr/lib/libgd.so.2 #4
>  0x000000000047e890 in msCleanup () #5  0x000000000044b4d0 in
> msCleanupOnSignal () #6  <signal handler called>
> #7  0x00007fdfa154b538 in TT_RunIns () from /usr/lib/libfreetype.so.6
> #8  0x00007fdfa1546073 in ?? () from /usr/lib/libfreetype.so.6
> #9  0x00007fdfa154edc1 in ?? () from /usr/lib/libfreetype.so.6
> #10 0x00007fdfa154f47d in ?? () from /usr/lib/libfreetype.so.6
> #11 0x00007fdfa153b4aa in FT_Load_Glyph ()
> from /usr/lib/libfreetype.so.6 #12 0x00007fdfa19eccb3 in
> gdImageStringFTEx () from /usr/lib/libgd.so.2 #13 0x00007fdfa19ed89b
> in gdImageStringFT () from /usr/lib/libgd.so.2 #14 0x00000000004cd151
> in msDrawTextLineGD () #15 0x000000000057de7e in msDrawTextLine ()
> #16 0x00000000004b8286 in msDrawLabelCache ()
> #17 0x00000000004ad595 in msDrawMap ()
> #18 0x00000000005a6aea in msWMSGetMap ()
> #19 0x00000000005aa52d in msWMSDispatch ()
> #20 0x000000000050ce91 in msOWSDispatch ()
> #21 0x000000000044b8b8 in main ()
> 
> Patch for this problem is attached.
> 
> Lauri Nõmme



-- 
Stephan Holl <stephan.holl at intevation.de> | Tel.: +49 (0)541-33 508 3663
Intevation GmbH, Neuer Graben 17, 49074 OS  |  AG Osnabrück - HR B 18998
Geschäftsführer:  Frank Koormann, Bernhard Reiter, Dr. Jan-Oliver Wagner
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: not available
Url : http://lists.osgeo.org/pipermail/mapserver-dev/attachments/20120103/fa3c4799/signature.bin