On Fri, 27 Nov 2015, Petr Mladek wrote:

MN10300 has its own implementation for entering and exiting NMI 
handlers. It does not call nmi_enter() and nmi_exit(). Please, find 
below an updated patch that adds printk_nmi_enter() and 
printk_nmi_exit() to the custom entry points. Then we could add HAVE_NMI 
to arch/mn10300/Kconfig and avoid the above warning.

Hmm, so what exactly would go wrong if MN10300 (whatever that architecture 
is) would call nmi_enter() and nmi_exit() at the places where it's 
starting and finishing NMI handler?

From a cursory look, it seems like most (if not all) of the things called 

from nmi_{enter,exit}() would be nops there anyway.

Thanks,

-- 
Jiri Kosina
SUSE Labs