Why does a RHEL5 KVM guest kernel panics on boot with the message "IO-APIC + timer doesn't work!"?

Solution Unverified - Updated -


  • The KVM guest kernel intermittently panics on boot with the below message.

    "Kernel panic - not syncing: IO-APIC + timer doesn't work! Try using the 'noapic' kernel parameter"


  • Red Hat Enterprise Linux 5 x86_64 KVM guest.
  • kernel version 2.6.18-274.18.1.el5 or earlier.
  • divider=10 in kernel boot command line.

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