4gb seg fixup errors on Debian Lenny Xen domU

I run CompleteFusion, and several other sites, on a virtual server hosted at VPSLink.  Recently, I upgraded the server from Debian Etch to Lenny.  After the upgrade, I've noticed errors like the following in the output from dmesg:

4gb seg fixup, process imap-login (pid 29663), cs:ip 73:002d9226
printk: 121 messages suppressed.

Some basic investigation revealed that this is apparently a fairly common issue with Xen domU instances, but it should be easy to fix:

  • First, make sure libc6-xen is installed: apt-get install libc6-xen
  • If /lib/tls exists on your system (it didn't on mine): mv /lib/tls /lib/tls.disabled
  • echo 'hwcap 0 nosegneg' > /etc/ld.so.conf.d/libc6-xen.conf && ldconfig
  • Reboot your domU

8 thoughts on “4gb seg fixup errors on Debian Lenny Xen domU

  1. Matthew

    Thanks for this. I'm also hosted on VPSLink and noticed my syslog filling up with the same error. The 'hwcap 0 nosegneg' bit did the trick for me.

  2. gumshoes

    I am curious about how you upgraded from etch to lenny on vpslink. Did you just re-install or did you mess with your sources.list and do a dist-upgrade?
    What I have found in the vpslink forums indicates that a dist-upgrade is not possible.

    Thanks.

  3. admin Post author

    @gumshoes: That's great that the upgrade worked for you. Looks like you're right about the kernel, as mine is still 2.6.18-53.1.13.el5xen

  4. Jonathan Addleman

    Just a quick note – if you copy and paste the commands as I did, they won't work because of the smartquotes that wordpress put in automatically. Make sure you use normal single-quotes around 'hwcap 0 nosegneg'.

    That "feature" has gotten in the way far too many times…

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