CPU "model 79" systems hangs/panics during boot following an update to the microcode_ctl package

Solution Verified - Updated -


  • After applying patches for CVE-2017-5754 CVE-2017-5753 and CVE-2017-5715, system poweroff during boot
  • After upgrade to microcode_ctl-1.17-25.2, the system is powered off during boot.
  • After update, the system hangs during boot with the following messages on the console:

    microcode: CPU0 sig=0x406f1, pf=0x1, revision=0xb00001f
    platform microcode: firmware: requesting intel-ucode/06-4f-01


  • Red Hat Enterprise Linux (RHEL) 7
  • Red Hat Enterprise Linux (RHEL) 6
  • microcode_ctl
  • Intel model 79 CPUs. The following models have been reported to experience the issue (not inclusive list)

    Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz
    Intel(R) Xeon(R) CPU E5-2643 v4 @ 3.40GHz
    Intel(R) Xeon(R) CPU E5-2667 v4 @ 3.20GHz
    Intel(R) Xeon(R) CPU E5-2667 v4 @ 3.50GHz

Subscriber exclusive content

A Red Hat subscription provides unlimited access to our knowledgebase of over 48,000 articles and solutions.

Current Customers and Partners

Log in for full access

Log In