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Date:   Fri, 25 Jan 2019 15:08:23 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Dave Young <dyoung@redhat.com>
Cc:     Pingfan Liu <kernelfans@gmail.com>, kexec@lists.infradead.org,
        Baoquan He <bhe@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>, yinghai@kernel.org,
        vgoyal@redhat.com, Randy Dunlap <rdunlap@infradead.org>,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCHv7] x86/kdump: bugfix, make the behavior of crashkernel=X
 consistent with kaslr
Message-ID: <20190125140823.GC27998@zn.tnic>
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 <20190125103924.GB27998@zn.tnic>
 <20190125134518.GA23595@dhcp-128-65.nay.redhat.com>
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On Fri, Jan 25, 2019 at 09:45:18PM +0800, Dave Young wrote:
> AFAIK, some people prefer to explictly reserve crash memory at high
> region even if it is possible to reserve at low area.  May because
> <4G memory is limited on large server, they want to leave this for other
> use. 
> 
> Yinghai or Vivek should know more about the history, probably they can
> recall some initial reason.

Yes, just "prefer" is not good enough. There should be a technical
reason why that's there.

Also, if the user doesn't care, then the code should be free to force
"high" and thus probe a different range for allocation.

> Good question, still it may be some historical reason, but it is good to
> make them clear and rethink about it after long time.
> 
> I also want to understand, need dig the log more.

Good idea. That would be a very nice cleanup. :-)

Thx.

-- 
Regards/Gruss,
    Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.