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Subject: Re: [PATCH 1/6] arm64/mm: Enable sysfs based memory hot add interface
To:     David Hildenbrand <david@redhat.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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        arunks@codeaurora.org, dan.j.williams@intel.com, osalvador@suse.de,
        logang@deltatee.com, pasha.tatashin@oracle.com, cai@lca.pw
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From:   Anshuman Khandual <anshuman.khandual@arm.com>
Message-ID: <fc9dadfa-6557-ecef-f027-7f3af098b55b@arm.com>
Date:   Thu, 4 Apr 2019 10:55:36 +0530
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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 wonder if we should try to do the same for the sysfs probing
> interface. Rather try to get rid of it than open the doors for more users.
> 

I understand your concern. Will drop this patch.