Tested on my family 10h processor.
The following settings:
```
$ sysctl hw.error_injection.dram_ecc
hw.error_injection.dram_ecc.inject: 0
hw.error_injection.dram_ecc.bit_mask: 8
hw.error_injection.dram_ecc.word_mask: 16
hw.error_injection.dram_ecc.quadrant: 1
```
Produced the following error after triggering the injection:
```
MCA: Bank 4, Status 0x9c0c4000a7080823
MCA: Global Cap 0x0000000000000106, Status 0x0000000000000000
MCA: Vendor "AuthenticAMD", ID 0x100f43, APIC ID 0
MCA: CPU 0 COR BUSLG Source WR Memory
MCA: Address 0x3a7654610
MCA: Misc 0xc01b0fff01000000
```
Post-processed with mcelog:
```
MCE 5
CPU 0 4 northbridge TSC 676d7e07481ba [at 3211 Mhz 6 days 13:24:22 uptime (unreliable)]
MISC c01b0fff01000000 ADDR 3a7654610
TIME 1488192936 Mon Feb 27 12:55:36 2017
Northbridge RAM Chipkill ECC error
Chipkill ECC syndrome = a718
bit46 = corrected ecc error
bit59 = misc error valid
bus error 'local node origin, request didn't time out
generic write mem transaction
memory access, level generic'
STATUS 9c0c4000a7080823 MCGSTATUS 0
MCGCAP 106 APICID 0 SOCKETID 0
CPUID Vendor AMD Family 16 Model 4
```