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	Fri, 11 Apr 2025 23:49:19 +0000
Date: Sat, 12 Apr 2025 00:49:18 +0100
From: Matthew Wilcox <willy@infradead.org>
To: Gregory Price <gourry@gourry.net>
Cc: linux-mm@kvack.org, cgroups@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com,
	akpm@linux-foundation.org, mingo@redhat.com, peterz@infradead.org,
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	hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev,
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	Huang Ying <ying.huang@linux.alibaba.com>,
	Keith Busch <kbusch@meta.com>, Feng Tang <feng.tang@intel.com>,
	Neha Gholkar <nehagholkar@meta.com>
Subject: Re: [RFC PATCH v4 0/6] Promotion of Unmapped Page Cache Folios.
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In-Reply-To: <20250411221111.493193-1-gourry@gourry.net>

On Fri, Apr 11, 2025 at 06:11:05PM -0400, Gregory Price wrote:
> Unmapped page cache pages can be demoted to low-tier memory, but

No.  Page cache should never be demoted to low-tier memory.
NACK this patchset.