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[156.34.48.30]) by smtp.gmail.com with ESMTPSA id h40sm827396qte.59.2020.10.02.04.39.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Oct 2020 04:39:45 -0700 (PDT) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1kOJPd-005Yy6-0U; Fri, 02 Oct 2020 08:39:45 -0300 Date: Fri, 2 Oct 2020 08:39:44 -0300 From: Jason Gunthorpe To: Michel Lespinasse Cc: Jann Horn , Andrew Morton , linux-mm , LKML , "Eric W . Biederman" , Mauro Carvalho Chehab , Sakari Ailus , Jeff Dike , Richard Weinberger , Anton Ivanov , linux-um@lists.infradead.org, John Hubbard Subject: Re: [PATCH 1/2] mmap locking API: Order lock of nascent mm outside lock of live mm Message-ID: <20201002113944.GH9916@ziepe.ca> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Oct 02, 2020 at 02:17:49AM -0700, Michel Lespinasse wrote: > Also FYI I was going to play with these patches a bit to help answer > these questions on my own, but wasn't able to easily apply them as > they came lightly mangled (whitespace issues) when I saved them. Me too It seems OK, you've created sort of a SINGLE_DEPTH_NESTING but in reverse - instead of marking the child of the nest it marks the parent. It would be nice to add a note in the commit message where the nesting happens on this path. Thanks, Jason