Apollo Lake with newer microcode: not affected by meltdown anymore?

From: Thomas Voegtle
Date: Tue Aug 28 2018 - 06:37:16 EST



Hello,

Kernel 4.18.5 with old microcode:

[ 0.000000] microcode: microcode updated early to revision 0x2c, date =
2017-03-25
cat /sys/devices/system/cpu/vulnerabilities/meltdown
Mitigation: PTI


Kernel 4.18.5 with new microcode (microcode-20180807.tgz), same config:

[ 0.000000] microcode: microcode updated early to revision 0x32, date =
2018-05-11
cat /sys/devices/system/cpu/vulnerabilities/meltdown
Not affected


This happens with 4.14.y and 4.9.y as well.

The same with ssb:
old microcode: spec_store_bypass:Vulnerable
new microcode: spec_store_bypass:Not affected

Is this intentional behavior? I have never seen this on other CPUs, such
as Gemini Lake or Baytrail, Haswell etc.

This is a Lenovo Ideapad 120S-11IAP with Apollo Lake N3350 (Goldmont)


Thomas