Re: [LSF/MM TOPIC] Discuss least bad options for resolving longterm-GUP usage by RDMA

From: Doug Ledford
Date: Wed Feb 06 2019 - 15:16:12 EST


On Wed, 2019-02-06 at 11:40 -0800, Matthew Wilcox wrote:
> On Wed, Feb 06, 2019 at 07:16:21PM +0000, Christopher Lameter wrote:
> >
> > though? If we only allow this use case then we may not have to worry about
> > long term GUP because DAX mapped files will stay in the physical location
> > regardless.
>
> ... except for truncate. And now that I think about it, there was a
> desire to support hot-unplug which also needed revoke.

We already support hot unplug of RDMA devices. But it is extreme. How
does hot unplug deal with a program running from the device (something
that would have returned ETXTBSY)?

--
Doug Ledford <dledford@xxxxxxxxxx>
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