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Date:   Fri, 2 Oct 2020 08:39:44 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Michel Lespinasse <walken@google.com>
Cc:     Jann Horn <jannh@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-mm <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Jeff Dike <jdike@addtoit.com>,
        Richard Weinberger <richard@nod.at>,
        Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        linux-um@lists.infradead.org, John Hubbard <jhubbard@nvidia.com>
Subject: Re: [PATCH 1/2] mmap locking API: Order lock of nascent mm outside
 lock of live mm
Message-ID: <20201002113944.GH9916@ziepe.ca>
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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