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identity=mailfrom; envelope-from=""; helo=NAM12-MW2-obe.outbound.protection.outlook.com; client-ip=40.107.244.87 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1617198367-64697 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Apr 01, 2021 at 12:27:52AM +1100, Alistair Popple wrote: > On Thursday, 1 April 2021 12:18:54 AM AEDT Jason Gunthorpe wrote: > > On Wed, Mar 31, 2021 at 11:59:28PM +1100, Alistair Popple wrote: > > > > > I guess that makes sense as the split could go either way at the > > > moment but I should add a check to make sure this isn't used with > > > pinned pages anyway. > > > > Is it possible to have a pinned page under one of these things? If I > > pin it before you migrate it then it remains pinned but hidden under > > the swap entry? > > At the moment yes. But I had planned (and this reminded me) to add a check to > prevent marking pinned pages for exclusive access. How do you even do that without races with GUP fast? Jason