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Howlett" , Alistair Popple Subject: Re: [PATCH] mm: Always sanity check anon_vma first for per-vma locks Message-ID: References: <20240410170621.2011171-1-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 6367C1A0008 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: y8g6c8uy84uxo4agh7huu6kgzja1f85w X-HE-Tag: 1712855648-903789 X-HE-Meta: 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 BEgzHbh2 G0iEVi5uqDGq/v5XVF637JTDJK9Jkjt+7Hv2yQnmARsJbTyk1s2+vFs7wI6BqqnwIi6QztynZYnZFMaP9Dst72jZfb7ILevI4j/D+SiTlZPa0JehlF97efd1Ny7JH6awRxwuvE6gZ6wB8nZBpDFwo/DcmOfdxMHutp/0PD6YRSkdeBGdUIf6ntlZL0g== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000009, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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.