From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
Subject: Re: Enabling peer to peer device transactions for PCIe devices
Date: Mon, 28 Nov 2016 15:24:52 -0700
Message-ID: <20161128222452.GA744@obsidianresearch.com>
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To: Serguei Sagalovitch <serguei.sagalovitch-5C7GfCeVMHo@public.gmane.org>
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On Mon, Nov 28, 2016 at 04:55:23PM -0500, Serguei Sagalovitch wrote:

> >We haven't touch this in a long time and perhaps it changed, but there
> >definitely was a call back in the PeerDirect API to allow the GPU to
> >invalidate the mapping. That's what we don't want.

> I assume that you are talking about "invalidate_peer_memory()' callback?
> I was told that it is the "last resort" because HCA (and driver) is not
> able to handle  it in the safe manner so it is basically "abort" everything.

If it is a last resort to save system stability then kill the impacted
process, that will release the MRs.

Jason