https://bugzilla.novell.com/show_bug.cgi?id=633978
https://bugzilla.novell.com/show_bug.cgi?id=633978#c0
Summary: NFS: soft lockup - CPU#0 stuck caused by simultaneous read/write on same file Classification: openSUSE Product: openSUSE 11.3 Version: Final Platform: x86-64 OS/Version: openSUSE 11.3 Status: NEW Severity: Critical Priority: P5 - None Component: Kernel AssignedTo: kernel-maintainers@forge.provo.novell.com ReportedBy: rhg@marxmeier.com QAContact: qa@suse.de Found By: --- Blocker: ---
Created an attachment (id=385013) --> (http://bugzilla.novell.com/attachment.cgi?id=385013) syslog messages after nfs soft lockup
User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8
I have a case where a soft lockup can be always reproduced.
System: HP Compaq dc5800 Microtower, Intel Core2 Duo CPU E8500 @ 3.16GHz openSUSE 11.3 x86_64, all patches applied Linux rhg-lx 2.6.34-12-default #1 SMP 2010-06-29 02:39:08 +0200 x86_64 x86_64 x86_64 GNU/Linux
To reproduce, a NFS mount is necessary.
Reproducible: Always
Steps to Reproduce: 1) I cd to a NFS mounted directory.
cd /some/nfs/mounted/directory
2) There, I do a recursive search for some text pattern with fgrep -r, such as:
fgrep -r 'Some Text' . >x1
As you see, by accident I write the fgrep result to a file which is located in the same directory where I do the recursive search. This is what causes the issue.
Note that the search pattern must match the text in at least some of the files located below the directory where I do the recursive search, so that something is written to the x1 file.
Almost immediately, the whole X session freezes, and after a minute a soft lockup message is written to the syslog (attached, see nfs-soft-lockup.txt file).