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charset=utf-8 Content-Disposition: inline X-Rspam-User: X-Rspamd-Queue-Id: 87588100002 X-Rspamd-Server: rspam03 X-Stat-Signature: 5p5k1kwtrkgek8u6x94qdkhcxe4j8yki X-HE-Tag: 1741977134-579454 X-HE-Meta: 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 Gm0atfNg 1W5GbMZzuAAnoCPcpHaPbz0ewrFCIsT1Qws7eCUvHn6bHiYacYOidDq0JpNd/DA0mYnGqhxksRSpdMGQ8smRUBkxxZSvfbD+Mu19odDjQrHGLAdOnQBoScBEDMJIl47+0FQIHO+8SU2vTcitedoZU1Eek7RYv/arE8bPTeen5lt4FFOwwP3+CA61QwN+wqIol6mRq+drLW/cG69fwKSQi7x7F99WR4mbjehMNunryhbDvmmrZ6A22sakOBI/FREI/rCZxRvXXTbKVdEeVTQoWec1Go7/BWRCKN2Nhp4ZMNudu8f6UmQi4CfaVtB/7uYn1gJpkq3DibNm7PoaPJYiBEFC5W+zrgKPxepR1QWXuL5yKF6gAtptx25KN4XQ0L5Mia/mr X-Bogosity: Ham, tests=bogofilter, spamicity=0.000957, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Mar 14, 2025 at 05:12:35PM +0000, Nikita Kalyazin wrote: > Yes, I was thinking about MADV_POPULATE_WRITE as well, but AFAIK it isn't > available in guest_memfd, at least with direct map removed due to [1] being > updated in [2]: I see, so GUP is no-go. IIUC the userapp can also prefault by writing zeros in a loop after mmap(). Thanks, -- Peter Xu