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Date: Mon, 9 Jan 2017 13:45:02 +0000
From: Matt Fleming <matt@codeblueprint.co.uk>
To: Mel Gorman <mgorman@techsingularity.net>
Cc: Dave Young <dyoung@redhat.com>, Nicolai Stange <nicstange@gmail.com>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>,
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        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@suse.cz>
Subject: Re: [PATCH v2 2/2] efi: efi_mem_reserve(): don't reserve through
 memblock after mm_init()
Message-ID: <20170109134502.GK16838@codeblueprint.co.uk>
References: <20161222102340.2689-1-nicstange@gmail.com>
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On Mon, 09 Jan, at 01:31:52PM, Mel Gorman wrote:
> 
> Well, you could put in a __init global variable about availability into
> mm/memblock.c and then check it in memblock APIs like memblock_reserve()
> to BUG_ON? I know BUG_ON is frowned upon but this is not likely to be a
> situation that can be sensibly recovered.

Indeed. I've only ever seen this situation lead to silent memory
corruption and bitter tears.