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From: Sasha Levin <sashal@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>,
	David Hildenbrand <david@kernel.org>,
	Lorenzo Stoakes <ljs@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>,
	Pedro Falcato <pfalcato@suse.de>,
	stable@vger.kernel.org,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>,
	Jan Kara <jack@suse.cz>,
	Matthew Wilcox <willy@infradead.org>,
	Song Liu <song@kernel.org>,
	Eric Hagberg <ehagberg@janestreet.com>,
	Zi Yan <ziy@nvidia.com>,
	Gregg Leventhal <gleventhal@janestreet.com>,
	Lance Yang <lance.yang@linux.dev>
Subject: Re: [PATCH stable v2] mm/khugepaged: write all dirty file folios when collapsing
Date: Wed,  8 Jul 2026 21:04:47 -0400
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> Fix it by fully writing back the page cache (and waiting) when collapsing
> file THPs. Doing so provides the guarantee that no dirty folio will be
> observed while there are active THPs. To fully ensure this is safe, the
> invalidate_lock needs to be held while doing the writeout, so that
> do_dentry_open()'s page cache truncation excludes this write-and-wait.

Queued for 7.1, 6.18, and 6.12 (with Willy's Reviewed-by and David's
Acked-by from this thread), thanks.

-- 
Thanks,
Sasha