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Date: Fri, 16 Oct 2026 15:55:34 +0100
From: "Lorenzo Stoakes (ARM)" <ljs@kernel.org>
To: Andrew Morton <akpm@linux-foundation.org>, 
	Suren Baghdasaryan <surenb@google.com>, "Liam R. Howlett" <liam@infradead.org>, 
	Vlastimil Babka <vbabka@kernel.org>, Shakeel Butt <shakeel.butt@linux.dev>, 
	David Hildenbrand <david@kernel.org>, Mike Rapoport <rppt@kernel.org>, Michal Hocko <mhocko@suse.com>, 
	Jonathan Corbet <corbet@lwn.net>, Randy Dunlap <rdunlap@infradead.org>, 
	Jann Horn <jannh@google.com>, Pedro Falcato <pfalcato@suse.de>
Cc: linux-mm@kvack.org, linux-doc@vger.kernel.org, 
	linux-kernel@vger.kernel.org, "Jose A. Perez de Azpillaga" <azpijr@gmail.com>, 
	Daehyeon Ko <4ncienth@gmail.com>
Subject: Re: [PATCH v2] mm/vma: avoid spurious write locks when
 mm->mm_lock_seq overflows
Message-ID: <atI6TVqoOhv0XMQ9@gremlin>
References: <20261016-fix-vma-lock-overflow-v2-1-9eb778b79b58@kernel.org>
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In-Reply-To: <20261016-fix-vma-lock-overflow-v2-1-9eb778b79b58@kernel.org>

On Fri, Oct 16, 2026 at 12:34:33PM +0100, Lorenzo Stoakes (ARM) wrote:

> Care must be taken, as resetting the sequence count at overflow means
> changing the seqcount of VMAs which are already attached and observable.

For the record, Liam pointed out the overflow as an issue on more than one
occasion in the past, and I (and I think others?) wrongly dismissed it at
the time, so full credit to Liam for raising it, and mea cupla to me for
not seeing it :P

That saying about assumptions etc. etc.

--
Cheers, Lorenzo