Hi Thomas,

Kernel build failed on

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git rcu/smp/hotplug
head:   34a6dd7090a665e2ce7b17f6097361c9e11dfca4
commit: e4bf0a283afe045c05947dc46fb7c995f6cc5fba [3/7] softirq: Use hotplug thread infrastructure
config: ia64-alldefconfig (attached as .config)

All related error/warning messages:

kernel/built-in.o: In function `spawn_ksoftirqd':
softirq.c:(.init.text+0xb92): undefined reference to `smpboot_register_percpu_thread'

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