2.6.18 nfs-client bug - files contains blocks of zeros

From: Kasparek Tomas
Date: Thu Sep 28 2006 - 06:10:15 EST

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I have the foloving setup:

- NFS clients machines running vanilla 2.6.18 (config included) writing on
NFS mounted share on several NFS server (inc. Lin, FreeBSD 6.1

- when two or more clients try to write/append to the same file on NFS
share this file contains all the data writen + some blocks are padded
with zeros.

- I used this test script:


while true; do
cat /tmp/data >>/pub/tmp/zeros.log
usleep 1000;

- /pub is the NFS share from Lin server
- resulting zeros.log is included

Expect it may be related to this:

([PATCH INTRO] Re: [RFC] copy_from_user races with readpage)

The same clients running are fine.

Is this known problem (have search vanila and nfs git repos but have not
found anything reasonable) or some new bug?

If you would like more infos please let me know.

(Please CC me as I'm not in the lists.)



Tomas Kasparek, PhD student E-mail: kasparek@xxxxxxxxxxxx
CVT FIT VUT Brno, BI/140a Web: http://www.fit.vutbr.cz/~kasparek
Bozetechova 2, 612 66 Fax: +420 54114-1270
Brno, Czech Republic Phone: +420 54114-1220

ICQ: 293092805 jabber: tomas.kasparek@xxxxxxxxx
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dnetc v2.9012-497-CFR-05111007 for Linux (Linux 2.6.18).
Using email address (distributed.net ID) 'tomas.kasparek@xxxxxxxxx'

[Sep 28 06:17:51 UTC] Automatic processor type detection found
an AMD K8-15 (Athlon 64) processor.
[Sep 28 06:17:51 UTC] OGR-P2: using core #3 (GARSP 6.0-asm-rt1-mmx).
[Sep 28 06:17:51 UTC] OGR-P2: Loaded 25/8-21-2-35-3-13 (25.00 Gnodes done)
[Sep 28 06:17:52 UTC] OGR-P2: 62 packets remain in buff-in.ogf
[Sep 28 06:17:52 UTC] OGR-P2: 0 packets are in buff-out.ogf
[Sep 28 06:17:52 UTC] 1 cruncher has been started.
[Sep 28 06:17:53 UTC] Shutdown - reached time limit.
[Sep 28 06:17:53 UTC] OGR-P2: Saved 25/8-21-9-11-31-2 (19.86 Gnodes done)
0.00:08:50.35 - [24,863,350 nodes/s]
[Sep 28 06:17:53 UTC] OGR-P2: Summary: 1 packet (3.30 stats units)
0.00:02:12.88 - [23.81 Mnodes/s]
[Sep 28 06:17:53 UTC] OGR-P2: 63 packets are in buff-in.ogf
[Sep 28 06:17:53 UTC] OGR-P2: 0 packets are in buff-out.ogf
[Sep 28 06:17:53 UTC] *Break* Shutting down...
[Sep 28 06:17:53 UTC] Shutdown complete.
[Sep 28 06:17:54 UTC] Shutdown - reached time limit.
[Sep 28 06:17:54 UTC] OGR-P2: Saved 25/8-21-9-5-31-11 (18.88 Gnodes done)
0.00:10:04.53 - [24,760,670 nodes/s]
[Sep 28 06:17:54 UTC] OGR-P2: 64 packets are in buff-in.ogf
[Sep 28 06:17:54 UTC] OGR-P2: 0 packets are in buff-out.ogf
[Sep 28 06:17:54 UTC] *Break* Shutting down...
[Sep 28 06:17:54 UTC] Shutdown complete.

Attachment: zeros.log-bad
Description: Binary data