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Subject: Re: [RFC PATCH v2 2/2] Architecture defined limit on memory region
 random shift.
From:   Ilya Smith <blackzert@gmail.com>
In-Reply-To: <20180322135448.046ada120ecd1ab3dd8f94aa@linux-foundation.org>
Date:   Fri, 23 Mar 2018 20:49:03 +0300
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To:     Andrew Morton <akpm@linux-foundation.org>
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> On 22 Mar 2018, at 23:54, Andrew Morton <akpm@linux-foundation.org> =
wrote:
>=20
>=20
> Please add changelogs.  An explanation of what a "limit on memory
> region random shift" is would be nice ;) Why does it exist, why are we
> doing this, etc.  Surely there's something to be said - at present =
this
> is just a lump of random code?
>=20
>=20
>=20
Sorry, my bad. The main idea of this limit is to decrease possible =
memory=20
fragmentation. This is not so big problem on 64bit process, but really =
big for=20
32 bit processes since may cause failure memory allocation. To control =
memory=20
fragmentation and protect 32 bit systems (or architectures) this limit =
was=20
introduce by this patch. It could be also moved to CONFIG_ as well.=