Hi NeilBrown,

Kernel build failed on

tree:   git://neil.brown.name/md for-next
head:   6db16051b04957b8e7e60c21b43e4b54ed927b46
commit: b774e8d8414b3e25fcd9c96febb522519b17dbd6 [9/27] blk: centralize non-request unplug handling.
config: i386-randconfig-k003 (attached as .config)

All related error/warning messages:

ERROR: "blk_check_plugged" [drivers/md/raid456.ko] undefined!

(forgot to export the symbol)

---
0-DAY kernel build testing backend         Open Source Technology Centre
Fengguang Wu <wfg@linux.intel.com>                     Intel Corporation