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Date: Thu, 7 Mar 2024 12:02:24 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Zi Yan <ziy@nvidia.com>
Cc: Zi Yan <zi.yan@sent.com>, linux-mm@kvack.org, Dan Carpenter
 <dan.carpenter@linaro.org>, "Pankaj Raghav (Samsung)"
 <kernel@pankajraghav.com>, "Matthew Wilcox (Oracle)" <willy@infradead.org>,
 David Hildenbrand <david@redhat.com>, Yang Shi <shy828301@gmail.com>, Yu
 Zhao <yuzhao@google.com>, "Kirill A . Shutemov"
 <kirill.shutemov@linux.intel.com>, Ryan Roberts <ryan.roberts@arm.com>,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] mm/huge_memory: check new folio order when split a
 folio
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On Thu,  7 Mar 2024 13:18:53 -0500 Zi Yan <zi.yan@sent.com> wrote:

> From: Zi Yan <ziy@nvidia.com>
> 
> A folio can only be split into lower orders. Check new_order to make sure
> it is smaller than input folio order.

It isn't clear what's being fixed here.  Presumably something is
passing in such folios, but what and where and why and what are the
effects?

Might it be that these folios are being caused by the debugfs
interface?  Or something else?

So I'll add it, but I do think more information and context would
improve the patch, please.  Suitable Reported-by:, Closes: and Link:
tags, perhaps.