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Date:   Wed, 31 Jul 2019 14:08:59 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Rashmica Gupta <rashmica.g@gmail.com>
Cc:     Oscar Salvador <osalvador@suse.de>,
        David Hildenbrand <david@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Dan Williams <dan.j.williams@intel.com>,
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        anshuman.khandual@arm.com, Vlastimil Babka <vbabka@suse.cz>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/5] Allocate memmap from hotadded memory
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On Tue 02-07-19 18:52:01, Rashmica Gupta wrote:
[...]
> > 2) Why it was designed, what is the goal of the interface?
> > 3) When it is supposed to be used?
> >
> >
> There is a hardware debugging facility (htm) on some power chips. To use
> this you need a contiguous portion of memory for the output to be dumped
> to - and we obviously don't want this memory to be simultaneously used by
> the kernel.

How much memory are we talking about here? Just curious.
-- 
Michal Hocko
SUSE Labs