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Subject: Re: [PATCH 1/6] arm64/mm: Enable sysfs based memory hot add interface
To:     Anshuman Khandual <anshuman.khandual@arm.com>,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-mm@kvack.org, akpm@linux-foundation.org, will.deacon@arm.com,
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From:   David Hildenbrand <david@redhat.com>
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Organization: Red Hat GmbH
Message-ID: <53c380bf-5896-69db-a054-eba1363fce66@redhat.com>
Date:   Thu, 4 Apr 2019 10:49:17 +0200
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On 04.04.19 07:25, Anshuman Khandual wrote:
> 
> 
> On 04/03/2019 01:50 PM, David Hildenbrand wrote:
>> On 03.04.19 06:30, Anshuman Khandual wrote:
>>> Sysfs memory probe interface (/sys/devices/system/memory/probe) can accept
>>> starting physical address of an entire memory block to be hot added into
>>> the kernel. This is in addition to the existing ACPI based interface. This
>>> just enables it with the required config CONFIG_ARCH_MEMORY_PROBE.
>>>
>> We recently discussed that the similar interface for removal should
>> rather be moved to a debug/test module.
> 
> Can we maintain such a debug/test module mainline and enable it when required. Or
> can have both add and remove interface at /sys/kernel/debug/ just for testing
> purpose.

I assume we could put such a module into mainline. It could span up an
interface in debugfs.

-- 

Thanks,

David / dhildenb