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j-g-faustus
Asked: 2011-03-14 12:19:25 +0800 CST

Can I block log messages from specific devices or drivers?

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I'm getting "NVRM: os_raise_smp_barrier()" messages in syslog and dmesg at a rate of 4-6 per minute; I think it's from the Nvidia graphics driver.

The system behaves normally, but the messages clutter up the logs so I can't find any real issues. (At the moment dmesg is 4,000 lines and 3,925 of those lines are the same message.)

Is it possible to suppress or redirect these messages?

Example log snippet:

Mar 13 20:38:04 desktop kernel: [175481.413559] NVRM: os_raise_smp_barrier(), invalid context!
Mar 13 20:38:04 desktop kernel: [175481.430904] NVRM: os_raise_smp_barrier(), invalid context!
Mar 13 20:38:45 desktop kernel: [175522.223337] NVRM: os_raise_smp_barrier(), invalid context!
Mar 13 20:38:45 desktop kernel: [175522.239655] NVRM: os_raise_smp_barrier(), invalid context!
Mar 13 20:38:47 desktop kernel: [175523.556706] NVRM: os_raise_smp_barrier(), invalid context!
Mar 13 20:38:47 desktop kernel: [175523.572015] NVRM: os_raise_smp_barrier(), invalid context!
10.10

1 Answers

  1. I have half an answer: I don't know how to block specific drivers, but rsyslog has a mechanism for filtering log messages on content:

    Edit the rsyslog configuration file:

    sudo nano /etc/rsyslog.d/50-default.conf

    Add a text filter at the top of the file, and redirect the messages matching the filter to a separate log:

    :msg, contains, "NVRM: os_raise_smp_barrier" -/var/log/junk.log
& ~

    Save the file and restart rsyslog:

    sudo service rsyslog restart

    Check that the restart worked:

    $ tail /var/log/syslog
...
Mar 14 10:38:35 desktop kernel: Kernel logging (proc) stopped.
Mar 14 10:38:35 desktop kernel: imklog 4.2.0, log source = /proc/kmsg started.
Mar 14 10:38:35 desktop rsyslogd: [origin software="rsyslogd" swVersion="4.2.0" x-pid="18494" x-info="http://www.rsyslog.com"] (re)start
Mar 14 10:38:35 desktop rsyslogd: rsyslogd's groupid changed to 103
Mar 14 10:38:35 desktop rsyslogd: rsyslogd's userid changed to 101

    And /var/log should now contain a new log file junk.log containing the filtered messages.

    So far so good, the only drawback is that it doesn't work for dmesg.

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