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Subject: Re: [PATCH 2/2] fadump: Disable deferred page struct initialisation
From: Balbir Singh <bsingharora@gmail.com>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>, linux-mm@kvack.org, Mel
 Gorman <mgorman@techsingularity.net>, Vlastimil Babka <vbabka@suse.cz>,
 Michal Hocko <mhocko@kernel.org>, Andrew Morton
 <akpm@linux--foundation.org>, Michael Ellerman <mpe@ellerman.id.au>,
 linuxppc-dev@lists.ozlabs.org
Date: Wed, 03 Aug 2016 15:20:42 +1000
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On Tue, 2016-08-02 at 18:49 +0530, Srikar Dronamraju wrote:
> Fadump kernel reserves significant number of memory blocks. On a multi-node
> machine, with CONFIG_DEFFERRED_STRUCT_PAGE support, fadump kernel fails to
> boot. Fix this by disabling deferred page struct initialisation.
> 

How much memory does a fadump kernel need? Can we bump up the limits depending
on the config. I presume when you say fadump kernel you mean kernel with
FADUMP in the config?

BTW, I would much rather prefer a config based solution that does not select
DEFERRED_INIT if FADUMP is enabled.

Balbir