On 9/19/18 1:55 AM, Christoph wrote:
Hi
can someone say me how to update the µcode of the cpu with xen?
I have added the ucode=scan parameter to xen but it does not seem to work...
the µcode version of my xeon is really old :/
model name : Intel(R) Xeon(R) CPU E3-1271 v3 @ 3.60GHz microcode : 0x10
There is a "caveat" in the current version of microcode_ctl which means it doesn't automatically install the microcode into the initramfs if the kernel isn't "known good" because of various issues with Linux kernel patches being needed for certain microcode features. There is a quick way to get it to force the microcode into the initramfs of any kernel:
mkdir -p /etc/microcode_ctl/ucode_with_caveats/ touch /etc/microcode_ctl/ucode_with_caveats/force
This only works with the most recent version of microcode_ctl (2.1-29.16.el7_5.x86_64). If you do this, you can then run 'yum reinstall microcode_ctl' and you should get the microcode in the initramfs after it finishes. Note that this will cause it to trust ALL kernels and all microcode versions which might not always be a good thing. See this file for info:
/usr/share/doc/microcode_ctl/README.caveats
You can test that the initramfs has the microcode by running cpio:
cpio -t < /boot/initramfs-4.9.112-32.el7.x86_64.img
If there is a GenuineIntel.bin you should be good. If you get spammed with errors, then it isn't included.