[PATCH] config, x86 enable boot cpu hotplug

[Prarit Bhargava]

On 01/14/2014 08:40 AM, Josh Boyer wrote:
> On Tue, Jan 14, 2014 at 7:36 AM, Prarit Bhargava <prarit at redhat.com> wrote:
>> Set CONFIG_BOOTPARAM_HOTPLUG_CPU0 to 'y'.  Currently, to disable CPU0,
>> the "boot" cpu, one must specify cpu0_hotplug as a kernel parameter.
>> Setting this config variable to 1 enables it by default.
>>
>> I've tested this on systems where it was expected to work and it seems to
>> function properly.
> 
> Looking this over, it simply makes it _possible_ to offline CPU0, but
> doesn't do it by default, correct?

Yes, that is correct.  You still have to manually echo 0 into
/sys/devices/system/cpu/cpu0/online to disable CPU 0.

> 
> I've got it queued locally and assuming the answer to my question is
> what I think it is, I'll push it out soonish.  Thanks.
> 

Thanks :)

P.

> josh