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dkim=pass header.d=Nvidia.com header.s=selector2 header.b=VqelS0Ok; spf=none (imf21.hostedemail.com: domain of jgg@nvidia.com has no SPF policy when checking 40.107.94.58) smtp.mailfrom=jgg@nvidia.com; dmarc=pass (policy=reject) header.from=nvidia.com X-Rspamd-Server: rspam06 X-HE-Tag: 1644597941-484480 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000004, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Feb 11, 2022 at 05:15:25PM +0100, David Hildenbrand wrote: > ... I'm pretty sure we cannot FOLL_PIN DEVICE_PRIVATE pages Currently the only way to get a DEVICE_PRIVATE page out of the page tables is via hmm_range_fault() and that doesn't manipulate any ref counts. Jason