Comment # 3 on bug 1040766 from Borislav Petkov

A couple of things:

Is there a newer BIOS for your box, i.e., newer than what you have now:

[gio mag 25 10:50:09 2017] DMI: Dell Inc. Precision Tower 3620/0MWYPT, BIOS
2.1.9 01/24/2017

?

Look at the manufacturer's website and if yes, try to update it to see
whether the MCEs disappear.

2. Does this box freeze at some point and you have to reboot it?

3. The MCE error information doesn't tell me a whole lot. Tony, can you
please take a look?

That's a KBL desktop, that address in ADDR looks like some hidden
device is doing something funny. And those MCEs all have PCC=1b so they
should've rebooted the box...

Hmmm.

Hardware event. This is not a software error.
CPU 0 BANK 6 
MISC 7880010086 ADDR fef1ffc0 
TIME 1495697460 Thu May 25 09:31:00 2017
MCG status:
MCi status:
Error overflow
Uncorrected error
MCi_MISC register valid
MCi_ADDR register valid
Processor context corrupt
MCA: corrected filtering (some unreported errors in same region)
Generic CACHE Level-2 Generic Error
STATUS ee0000000040110a MCGSTATUS 0
CPUID Vendor Intel Family 6 Model 158
(Fields were incomplete)
SOCKET 0 APIC 0 microcode 48
Hardware event. This is not a software error.
CPU 0 BANK 7 
MISC 3880010086 ADDR fef200c0 
TIME 1495697460 Thu May 25 09:31:00 2017
MCG status:
MCi status:
Error overflow
Uncorrected error
MCi_MISC register valid
MCi_ADDR register valid
Processor context corrupt
MCA: corrected filtering (some unreported errors in same region)
Generic CACHE Level-2 Generic Error
STATUS ee0000000040110a MCGSTATUS 0
CPUID Vendor Intel Family 6 Model 158
SOCKET 0 APIC 0 microcode 48
Hardware event. This is not a software error.
CPU 0 BANK 8 
MISC 43880010086 ADDR fef1ce80 
TIME 1495697460 Thu May 25 09:31:00 2017
MCG status:
MCi status:
Error overflow
Uncorrected error
MCi_MISC register valid
MCi_ADDR register valid
Processor context corrupt
MCA: corrected filtering (some unreported errors in same region)
Generic CACHE Level-2 Generic Error
STATUS ee0000000040110a MCGSTATUS 0
CPUID Vendor Intel Family 6 Model 158
SOCKET 0 APIC 0 microcode 48
Hardware event. This is not a software error.
CPU 0 BANK 9 
MISC 3880010086 ADDR fef1ff00 
TIME 1495697460 Thu May 25 09:31:00 2017
MCG status:
MCi status:
Error overflow
Uncorrected error
MCi_MISC register valid
MCi_ADDR register valid
Processor context corrupt
MCA: corrected filtering (some unreported errors in same region)
Generic CACHE Level-2 Generic Error
STATUS ee0000000040110a MCGSTATUS 0
CPUID Vendor Intel Family 6 Model 158
SOCKET 0 APIC 0 microcode 48