Re: [PATCH] x86, acpi memory hotplug, add parameter to disable memory hotplug

Prarit Bhargava
2014-01-14T11:05:31Z

On 01/13/2014 08:41 PM, Toshi Kani wrote:
> On Tue, 2014-01-14 at 10:11 +0900, Yasuaki Ishimatsu wrote:
> :
>>>> I think we need a knob manually enable mem-hotplug when specify memmap. But
>>>> it is another story.
>>>>
>>>> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
>>>
>>> As mentioned, self-NAK. I have seen a system that I needed to specify
>>> memmap=exactmap & had hotplug memory. I will only keep the acpi_no_memhotplug
>>> option in the next version of the patch.
>>
>>
>> Your following first patch is simply and makes sense.
>>
>> http://marc.info/?l=linux-acpi&m=138922019607796&w=2
>>
>
> In this option, it also requires changing kexec-tools to specify the new
> option for kdump. It won't be simpler.

It will be simpler for the kernel and those of us who have to debug busted e820
maps ;)

Unfortunately I may not be able to give you the automatic disable. I did
contemplate adding a !is_kdump_kernel() to the ACPI memory hotplug init call,
but it seems like that is unacceptable as well.

P.

>
> Thanks,
> -Toshi