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Date:   Mon, 28 Sep 2020 19:51:07 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Peter Xu <peterx@redhat.com>, Leon Romanovsky <leonro@nvidia.com>,
        John Hubbard <jhubbard@nvidia.com>,
        Linux-MM <linux-mm@kvack.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jan Kara <jack@suse.cz>, Michal Hocko <mhocko@suse.com>,
        Kirill Tkhai <ktkhai@virtuozzo.com>,
        Kirill Shutemov <kirill@shutemov.name>,
        Hugh Dickins <hughd@google.com>,
        Christoph Hellwig <hch@lst.de>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Oleg Nesterov <oleg@redhat.com>, Jann Horn <jannh@google.com>
Subject: Re: [PATCH 1/5] mm: Introduce mm_struct.has_pinned
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On Mon, Sep 28, 2020 at 12:50:03PM -0700, Linus Torvalds wrote:

> But the more I look at this code, the more I go "ok, I want somebody
> to actually test this with the rdma case".

I suspect it will be OK as our immediate test suite that touches this
will be using malloc memory.

It seems some mmap trick will be needed to get higher map counts?

> So I'll attach my suggested patch, but I won't actually commit it. I'd
> really like to have this tested, possibly _together_ with the sequence
> count addition..

Ok, we will do this once the holidays are over. If Peter doesn't take
it I can look at the seqcount too.

Thanks,
Jason