I'm seeing these MCE messages too. My hardware is i7 4790K on a Gigabyte Z97X Gaming GT motherboard.
I run a mixture of Linux and Windows (client and server editions) guests. Hipervisor is kvm. I'm seeing these MCE messages since I virtualized a Windows Server 2008 R2 SP1. Neither Windows XP nor Windows 8.1 guests showed any messages. For a few minutes I was worried my hardware was faulty, but this bug reports somewhat gives me hope the hardware is OK. Pasted below is my /var/log/mcelog mcelog: failed to prefill DIMM database from DMI data Hardware event. This is not a software error. MCE 0 CPU 0 BANK 0 TIME 1440943174 Sun Aug 30 10:59:34 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 0 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 1 CPU 0 BANK 0 TIME 1441015741 Mon Aug 31 07:09:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 0 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 0 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 1 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 2 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 3 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 4 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 5 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 6 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 7 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 8 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 9 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 10 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 11 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 12 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 13 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 0 CPU 2 BANK 0 TIME 1441064341 Mon Aug 31 20:39:01 2015 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 Hardware event. This is not a software error. MCE 0 CPU 2 BANK 0 TIME 1441064371 Mon Aug 31 20:39:31 2015 MCG status: MCi status: Error overflow Corrected error Error enabled MCA: Internal parity error STATUS d0000200000f0005 MCGSTATUS 0 MCGCAP c09 APICID 4 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1307225 Title: Running a virtual machine on a Haswell system produces machine check events Status in QEMU: New Bug description: I'm running a virtual Windows SBS 2003 installation on a Xeon E3 Haswell system running Gentoo Linux. First, I used Qemu 1.5.3 (the latest stable version on Gentoo). I got a lot of machine check events ("mce: [Hardware Error]: Machine check events logged") in dmesg that always looked like (using mcelog): Hardware event. This is not a software error. MCE 0 CPU 3 BANK 0 TIME 1397455091 Mon Apr 14 07:58:11 2014 MCG status: MCi status: Corrected error Error enabled MCA: Internal parity error STATUS 90000040000f0005 MCGSTATUS 0 MCGCAP c09 APICID 6 SOCKETID 0 CPUID Vendor Intel Family 6 Model 60 I found this discussion on the vmware community: https://communities.vmware.com/thread/452344 It seems that this is (at least partly) caused by the Qemu machine. I switched to Qemu 1.7.0, the first version to use "pc-i440fx-1.7". With this version, the errors almost disappeared, but from time to time, I still get machine check events. Anyways, they so not seem to affect neither the vm, nor the host. The Haswell machine has been set up and running for several days without a single error message. They only appear when the VM is running. so I think this is actually some problem with the Haswell architecture (and not a real hardware error). To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1307225/+subscriptions
