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Date: Thu, 11 Apr 2024 18:14:05 +0100
From: Matthew Wilcox <willy@infradead.org>
To: Peter Xu <peterx@redhat.com>
Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Suren Baghdasaryan <surenb@google.com>,
	Lokesh Gidra <lokeshgidra@google.com>,
	"Liam R . Howlett" <Liam.Howlett@oracle.com>,
	Alistair Popple <apopple@nvidia.com>
Subject: Re: [PATCH] mm: Always sanity check anon_vma first for per-vma locks
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References: <20240410170621.2011171-1-peterx@redhat.com>
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On Thu, Apr 11, 2024 at 11:34:44AM -0400, Peter Xu wrote:
>    If the answer is yes, I'd say please provide some document patch to
>    support such behavior, you can stop my patch from getting merged now,
>    but it's never clear whether someone else will see this and post it
>    again.  If it wasn't obviously to Suren who introduced per-vma lock [1],
>    then I won't be surprised it's unknown to most developers on the list.

Anyone touching this path should have a good idea about what is and is
not the common case.  Your confidence greatly exceeded your ability
here.  I will not be submitting such a patch.