(.text+0x17196): undefined reference to `bh_check_bridge'

Hi Bjorn,

FYI, kernel build failed on

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git bug/kbz46481
head:   54a2804aaa64648d842486ec49237583b198b41c
commit: 54a2804aaa64648d842486ec49237583b198b41c [2/2] debug
config: x86_64-allmodconfig # make ARCH=x86_64 
branch date: 3 days ago
commit date: 3 days ago

All error/warnings:

drivers/built-in.o: In function `pci_create_slot':
(.text+0x17196): undefined reference to bh_check_bridge' drivers/built-in.o: In function pci_create_slot':
(.text+0x1730d): undefined reference to bh_check_bridge' drivers/built-in.o: In function pci_create_slot':
(.text+0x173f3): undefined reference to bh_check_bridge' drivers/built-in.o: In function pci_create_slot':
(.text+0x1749d): undefined reference to bh_check_bridge' drivers/built-in.o: In function pci_create_slot':
(.text+0x1752e): undefined reference to `bh_check_bridge'

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0-DAY kernel build testing backend Open Source Technology Center
Fengguang Wu, Yuanhan Liu Intel Corporation