Comment 2 for bug 1670137

Occurs while suspend to ram, attempted pm_trace (sudo sh -c "sync && echo 1 > /sys/power/pm_trace && pm-suspend"):
...
[ 1.196689] Key type encrypted registered
[ 1.196712] AppArmor: AppArmor sha1 policy hashing enabled
[ 1.442937] evm: HMAC attrs: 0x1
[ 1.444273] Magic number: 12:578:178
[ 1.444323] acpi device:0e: hash matches
[ 1.444345] platform: hash matches
[ 1.444671] rtc_cmos 00:02: setting system clock to 2016-12-22 12:09:40 UTC (1482408580)
[ 1.444925] BIOS EDD facility v0.16 2004-Jun-25, 0 devices found
[ 1.444927] EDD information not available.
[ 1.445014] PM: Hibernation image not present or could not be loaded.
[ 1.445962] Freeing unused kernel memory: 1480K (ffffffff81f42000 - ffffffff820b4000)
...

More data points:
  https://errors.ubuntu.com/oops/3a52bdf6-01b6-11e7-b175-fa163e839e11
  https://errors.ubuntu.com/oops/8423d2c6-01b6-11e7-84d4-fa163ebeb28a