Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 22 Dec 2012 10:07:54 -0500
From:      "Mikhail T." <mi+thun@aldan.algebra.com>
To:        stable@FreeBSD.org
Subject:   xz(1) keeps SEGFAULT-ing
Message-ID:  <50D5CCCA.2050000@aldan.algebra.com>

next in thread | raw e-mail | index | archive | help
Hello!

I've set up several nightly backups all using the pipe-chain of dump | 
xz -9 | ccrypt > /remote/backups/fs.xz.cpt

On one system these just work every night without a problem. On another 
I see xz SEGFAULT-ing about 90% through almost every night for one of 
the filesystems (the bigger of the two). This is, what cron emails me:

       DUMP: WARNING: should use -L when dumping live read-write filesystems!
       DUMP: Date of this level 1 dump: Sat Dec 22 03:23:00 2012
       DUMP: Date of last level 0 dump: Thu Dec  6 01:23:02 2012
       DUMP: Dumping /dev/ad4s1g (/home) to standard output
       DUMP: mapping (Pass I) [regular files]
       DUMP: Cache 16 MB, blocksize = 65536
       DUMP: mapping (Pass II) [directories]
       DUMP: estimated 2157823 tape blocks.
       DUMP: dumping (Pass III) [directories]
       DUMP: dumping (Pass IV) [regular files]
       DUMP: 11.50% done, finished in 0:38 at Sat Dec 22 04:07:55 2012
       DUMP: 17.80% done, finished in 0:46 at Sat Dec 22 04:20:37 2012
       DUMP: 24.32% done, finished in 0:46 at Sat Dec 22 04:26:05 2012
       DUMP: 31.23% done, finished in 0:44 at Sat Dec 22 04:28:27 2012
       DUMP: 36.16% done, finished in 0:44 at Sat Dec 22 04:33:34 2012
       DUMP: 43.21% done, finished in 0:39 at Sat Dec 22 04:33:51 2012
       DUMP: 54.86% done, finished in 0:28 at Sat Dec 22 04:28:14 2012
       DUMP: 60.63% done, finished in 0:25 at Sat Dec 22 04:30:24 2012
       DUMP: 65.83% done, finished in 0:23 at Sat Dec 22 04:32:47 2012
       DUMP: 70.54% done, finished in 0:20 at Sat Dec 22 04:35:18 2012
       DUMP: 75.15% done, finished in 0:18 at Sat Dec 22 04:37:37 2012
       DUMP: 80.28% done, finished in 0:14 at Sat Dec 22 04:39:10 2012
       DUMP: 85.57% done, finished in 0:10 at Sat Dec 22 04:40:23 2012
       DUMP: 90.50% done, finished in 0:07 at Sat Dec 22 04:41:46 2012
       DUMP: SIGSEGV: ABORTING!
       DUMP:   DUMP:   DUMP: SIGSEGV: ABORTING!
    SIGSEGV: ABORTING!
    SIGSEGV: ABORTING!
       DUMP: SIGSEGV: ABORTING!

Following xz's fault, all other processes (dump, ccrypt, sh) dump their 
cores to, but, according to dmesg, the culprit is always xz. According 
to core, the fault is somewhere inside liblzma.so.5. I recompiled the 
library to enable debugging and am trying to investigate, but, perhaps, 
someone has already run into this?

Both systems used to run FreeBSD-8/amd64, when I first set the jobs up. 
I have since upgraded the troublesome server to 9.1, but that did not 
fix the problem.

The remote filesystem (where ccrypt writes encrypted output) is mounted 
via smbfs on both servers, but I doubt that matters...

Any ideas? Thanks,

    -mi




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?50D5CCCA.2050000>