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Subject: Re: [PATCH 1/4] mm: Provide kernel parameter to allow disabling page
 init poisoning
References: <20180910232615.4068.29155.stgit@localhost.localdomain>
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 <20180912141053.GL10951@dhcp22.suse.cz>
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From: Dave Hansen <dave.hansen@intel.com>
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Date: Wed, 12 Sep 2018 09:43:27 -0700
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To: Alexander Duyck <alexander.duyck@gmail.com>, mhocko@kernel.org, pavel.tatashin@microsoft.com, dan.j.williams@intel.com
Cc: linux-mm <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>, linux-nvdimm@lists.01.org, dave.jiang@intel.com, Ingo Molnar <mingo@kernel.org>, jglisse@redhat.com, Andrew Morton <akpm@linux-foundation.org>, logang@deltatee.com, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>

On 09/12/2018 09:36 AM, Alexander Duyck wrote:
>>         vm_debug =      [KNL] Available with CONFIG_DEBUG_VM=y.
>>                         May slow down boot speed, especially on larger-
>>                         memory systems when enabled.
>>                         off: turn off all runtime VM debug features
>>                         all: turn on all debug features (default)
> This would introduce a significant amount of code change if we do it
> as a parameter that has control over everything.

Sure, but don't do that now.  Just put page poisoning under it now.