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Date:   Fri, 13 Nov 2020 03:49:25 +0000 (GMT)
From:   "Maciej W. Rozycki" <macro@linux-mips.org>
To:     Jinyang He <hejinyang@loongson.cn>
cc:     Jiaxun Yang <jiaxun.yang@flygoat.com>,
        Serge Semin <fancer.lancer@gmail.com>,
        Alexander Sverdlin <alexander.sverdlin@nokia.com>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        linux-mips@vger.kernel.org, Paul Burton <paulburton@kernel.org>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] MIPS: reserve the memblock right after the kernel
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Message-ID: <alpine.LFD.2.21.2011130339250.4064799@eddie.linux-mips.org>
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On Fri, 13 Nov 2020, Jinyang He wrote:

> Commit: d3ff93380232 (mips: Make sure kernel memory is in iomem)
> As I thought, this check is related to kdump. More directly, it is
> related to the "mem=" parameter. Kexec-tools provide a "mem=" parameter
> to limit the kernel location in kdump. But sometimes the memory may be not
> enough and this check gives a way to ensure the capture kernel can
> start rightly. Although "mem=" is not in kexec-tools now, I thought
> it is also useful if someone use "mem=" to do other things.

 I used to supply `mem=' by hand on many occasions across different MIPS 
systems and for various reasons over the last 20 years; surely before 
kexec was even thought of.  The option itself has been there in the MIPS 
port since I added it to Linux 2.4.0 back in Dec 2000.

  Maciej