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Date: Mon, 21 May 2018 13:59:01 +0000
From: Christopher Lameter <cl@linux.com>
Subject: Re: [LSFMM] RDMA data corruption potential during FS writeback
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To: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>, Jason Gunthorpe <jgg@ziepe.ca>, linux-rdma <linux-rdma@vger.kernel.org>, Linux MM <linux-mm@kvack.org>, Michal Hocko <mhocko@kernel.org>

On Fri, 18 May 2018, John Hubbard wrote:

> > In other words, get_user_pages_longterm() is just a short term
> > band-aid for RDMA until we can get that infrastructure built. We don't
> > need to go down any mmu-notifier rabbit holes.
> >
>
> git grep claims that break_layouts is so far an XFS-only feature, though.
> Were there plans to fix this for all filesystems?

break_layouts? This sounds from my perspective like a mmu notifier
callback with slightly different semantics. Maybe add another callback to
generalize that functionality?