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Date:   Tue, 12 Feb 2019 16:36:36 +0000
From:   Christopher Lameter <cl@linux.com>
To:     Dan Williams <dan.j.williams@intel.com>
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        John Hubbard <jhubbard@nvidia.com>,
        Jerome Glisse <jglisse@redhat.com>,
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Subject: Re: [LSF/MM TOPIC] Discuss least bad options for resolving longterm-GUP
 usage by RDMA
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On Mon, 11 Feb 2019, Dan Williams wrote:

> An mmap write after a fault due to a hole punch is free to trigger
> SIGBUS if the subsequent page allocation fails. So no, I don't see
> them as the same unless you're allowing for the holder of the MR to
> receive a re-fault failure.

Order 0 page allocation failures are generally not possible in that path.
System will reclaim and OOM before that happens.