Hi Randy,

On Fri, 27 Nov 2020 07:57:32 -0800 Randy Dunlap <rdunlap@infradead.org> wrote:
>
> On 11/27/20 1:04 AM, Stephen Rothwell wrote:
> > Hi all,
> > 
> > Changes since 20201126:
> >   
> 
> (This looks strange to me.)
> 
> 
> on i386 or x86_64:
> 
> # CONFIG_ACPI is not set
> 
> ../drivers/idle/intel_idle.c: In function ‘intel_idle_init_cstates_icpu’:
> ../drivers/idle/intel_idle.c:1510:7: error: implicit declaration of function ‘intel_idle_state_needs_timer_stop’; did you mean ‘intel_idle_init_cstates_icpu’? [-Werror=implicit-function-declaration]
>    if (intel_idle_state_needs_timer_stop(&drv->states[drv->state_count]))
>        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

intel_idle_state_needs_timer_stop() is only defined when
CONFIG_ACPI_PROCESSOR_CSTATE is set, but is used once where that is not
necessarily set.  I assume CONFIG_ACPI_PROCESSOR_CSTATE is not set in
your config?

Caused by commit

  6e1d2bc675bd ("intel_idle: Fix intel_idle() vs tracing")

from the tip tree.
-- 
Cheers,
Stephen Rothwell