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Date:   Wed, 18 Nov 2020 19:15:29 +0000
From:   Will Deacon <will@kernel.org>
To:     Mike Rapoport <rppt@kernel.org>
Cc:     Barry Song <song.bao.hua@hisilicon.com>, catalin.marinas@arm.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        akpm@linux-foundation.org, anshuman.khandual@arm.com,
        linuxarm@huawei.com
Subject: Re: [PATCH] arm64: mm: add support for memmap kernel parameters
Message-ID: <20201118191528.GA2680@willie-the-truck>
References: <20201118063314.22940-1-song.bao.hua@hisilicon.com>
 <20201118173854.GA8537@kernel.org>
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On Wed, Nov 18, 2020 at 07:38:54PM +0200, Mike Rapoport wrote:
> On Wed, Nov 18, 2020 at 07:33:14PM +1300, Barry Song wrote:
> > memmap should be an useful kernel parameter which has been supported by
> > x86, mips and xtensa.
> 
> Why is this parameter should be useful for ARM64? 
> My understanding is that it is required only to work around really
> broken bootloaders, isn't it?

Agreed, I can't see this being something we really want to support. If it
turns out that it is generally useful, then the implementation should
probably be somewhere outside of arch/ where I don't have to look at it :)

Will