[elrepo] kernel-lt and microcode updates

[Phil Perry]

On 01/07/2020 17:49, Orion Poplawski wrote:
>>
>> I just re-installed kernel-lt on my laptop:
>>
>> # grep -i microcode dmesg-3.10.0-1127.13.1.el7.x86_64
>> [    0.000000] microcode: microcode updated early to revision 0xd6, 
>> date = 2020-04-27
>> [    0.021352] SRBDS: Mitigation: Microcode
>> [    1.542686] microcode: sig=0x806ea, pf=0x80, revision=0xd6
>> [    1.542918] microcode: Microcode Update Driver: v2.01 
>> <tigran at aivazian.fsnet.co.uk>, Peter Oruba
>>
>> # grep -i microcode dmesg-4.4.228-2.el7.elrepo.x86_64
>> [    0.035312] SRBDS: Vulnerable: No microcode
>> [    0.992458] microcode: CPU0 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992471] microcode: CPU1 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992491] microcode: CPU2 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992511] microcode: CPU3 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992530] microcode: CPU4 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992550] microcode: CPU5 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992569] microcode: CPU6 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992588] microcode: CPU7 sig=0x806ea, pf=0x80, revision=0xb4
>> [    0.992673] microcode: Microcode Update Driver: v2.01 
>> <tigran at aivazian.fsnet.co.uk>, Peter Oruba
>>
>> and /proc/cpuinfo indicates that microcode is not updated
>>
>> Orion
> 
> turning on dracut logging it apprears that:
> 
> I:     microcode_ctl: kernel version "4.4.228-2.el7.elrepo.x86_64" 
> failed early load check for "intel", skipping
> 
> I: *** Generating early-microcode cpio image contents ***
> I: *** No early-microcode cpio image needed ***
> 
> that check is done in /usr/libexec/microcode_ctl/check_caveats
> 
> that is for early loading.  not sure why the microcode.service also 
> seems to fail to load the firmware.
> 
> 

Interesting. Any idea why early updating appears to work on the distro 
kernel, but not for kernel-lt? I wonder what check it is failing.

I will try to run some more tests on my hardware to find out if it's 
specific to you/your hardware.