Messages in this thread | | | Date | Tue, 28 Aug 2018 14:35:18 +0200 (CEST) | From | Thomas Voegtle <> | Subject | Re: Apollo Lake with newer microcode: not affected by meltdown anymore? |
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On Tue, 28 Aug 2018, Thomas Gleixner wrote:
> On Tue, 28 Aug 2018, Thomas Voegtle wrote: >> 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. > > Looks like the micro code update has the relevant bits set in the > IA32_ARCH_CAPABILITIES MSR, which tell the kernel that the CPU is not > vulnerable. So it seems Intel was able to mitigate the mess in micro code > for this particular CPU model.
Ah, ok. Didn't think of the most obvious. But yes RDCL_NO is set to 1 with the new microcode. Wow.
Thanks and sorry for the noise,
Thomas
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