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Message-ID: <0e813c8498bf3d9ed5d8fd5b171ac9980dc2999c.camel@physik.fu-berlin.de>
Subject: Re: [PATCH v2] sh: Call paging_init() earlier in the init sequence
From: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
To: Oreoluwa Babatunde <quic_obabatun@quicinc.com>, 
	ysato@users.sourceforge.jp, dalias@libc.org
Cc: akpm@linux-foundation.org, linux-sh@vger.kernel.org, 
 linux-kernel@vger.kernel.org, robh+dt@kernel.org, kernel@quicinc.com, Rob
 Herring <robh@kernel.org>, Rob Landley <rob@landley.net>
Date: Wed, 08 May 2024 00:41:45 +0200
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References: <20240423233150.74302-1-quic_obabatun@quicinc.com>
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Hello Oreoluwa,

On Tue, 2024-05-07 at 14:42 -0700, Oreoluwa Babatunde wrote:
> memblock_alloc() marks all its allocations as reserved by calling
> memblock_reserve().
> https://elixir.bootlin.com/linux/latest/source/mm/memblock.c#L1463
>=20
> This should normally stop other users from allocating from within that
> region of memory.
>=20
> But in this case, since all the free memory regions have already been
> transferred over to the bootmem framework by paging_init(), I am not
> sure if that logic will still hold for the unflatten_deivcetree allocated=
 memory.
>=20
> The main goal of this patch is to make sure that the reserved memory
> regions defined in the DT are set aside before any memblock allocations
> are done (which includes the allocation done by unflatten_devicetree).
>=20
> Hence, I can restructure the patch to only remove the portion of code tha=
t is
> is responsible for setting aside the DT defined reserved memory regions f=
rom
> within paging_init(), and move it above the unflatten_devicetree() call.
> https://elixir.bootlin.com/linux/latest/source/arch/sh/mm/init.c#L292
>=20
> I will explore further and possibly restructure this patch based on my fi=
ndings.

OK, sounds like a plan. In the meantime, I have set up my J2 Turtle Board a=
nd
I am actually now able to test patches for this target, so that I would be
able to verify that your patch didn't break anything.

However, I think for v6.10 I think the ship has sailed.

Adrian

--=20
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
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