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Date: Mon, 11 Jun 2018 16:56:36 +0200
From: Michal Hocko <mhocko@kernel.org>
Subject: Re: [PATCH v2 00/11] mm: Teach memory_failure() about ZONE_DEVICE
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To: Dan Williams <dan.j.williams@intel.com>
Cc: linux-nvdimm <linux-nvdimm@lists.01.org>, linux-edac@vger.kernel.org, Tony Luck <tony.luck@intel.com>, Borislav Petkov <bp@alien8.de>, =?iso-8859-1?B?Suly9G1l?= Glisse <jglisse@redhat.com>, Jan Kara <jack@suse.cz>, "H. Peter Anvin" <hpa@zytor.com>, X86 ML <x86@kernel.org>, Thomas Gleixner <tglx@linutronix.de>, Christoph Hellwig <hch@lst.de>, Ross Zwisler <ross.zwisler@linux.intel.com>, Matthew Wilcox <mawilcox@microsoft.com>, Ingo Molnar <mingo@redhat.com>, Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>, Souptick Joarder <jrdr.linux@gmail.com>, Linux MM <linux-mm@kvack.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>

On Mon 11-06-18 07:44:39, Dan Williams wrote:
[...]
> I'm still trying to understand the next level of detail on where you
> think the design should go next? Is it just the HWPoison page flag?
> Are you concerned about supporting greater than PAGE_SIZE poison?

I simply do not want to check for HWPoison at zillion of places and have
each type of page to have some special handling which can get wrong very
easily. I am not clear on details here, this is something for users of
hwpoison to define what is the reasonable scenarios when the feature is
useful and turn that into a feature list that can be actually turned
into a design document. See the different from let's put some more on
top approach...

-- 
Michal Hocko
SUSE Labs