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See http://www.infradead.org/rpr.html X-Stat-Signature: pmoh9fg936u94iedykz5jusprkhsir9r X-Rspam-User: X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 8813A1C0005 X-HE-Tag: 1760682837-722248 X-HE-Meta: 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 G3L+sG1v x12MZuEw+roylsZ5Eb1y0FJBFtrUHqX4rzGVgK6m+slXIKHezAjN69yrc1RRfMitEsGYFkHLcQ50cXXDrkOv2QoPEGZQIwsQoAvUTYnc9OT7bF5m4Xi0UarWX142NAdDpzw23HwFcReOYcofTAmeQBdfyH0rxcDiljYGYXCYE9iewbhZ7zK1XP0coREhpKvai/0Ps6lEMHI1k33sqNR3jfN/5yNjnm5Ahx0zcIWbcli00AFBsgoaezOEwtEMGJelDIhMVvm3YdDX43ZjbbPja7l1bR3G7zW0z+3DY+kLD46usFPWPkc3eq9UGGQm8SnC5uf/EE6iU8I6w5SEarUZEHrfTdPVkelmPcBd7IJGi2ppLRnJMJj1ZYKWTP/np7Qdwb6V1feLxxPT3+f86OoznCQHd0w5wnThfs2g1huWqfwexExWaeJZMinMmGitsMyG0CbE6dJeL5PtMs9x2jDeqoz1N5mCd3FEsYMm3 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: List-Subscribe: List-Unsubscribe: On Mon, Oct 13, 2025 at 06:26:11PM +0300, Leon Romanovsky wrote: > From: Leon Romanovsky > > Add support for exporting PCI device MMIO regions through dma-buf, > enabling safe sharing of non-struct page memory with controlled > lifetime management. This allows RDMA and other subsystems to import > dma-buf FDs and build them into memory regions for PCI P2P operations. > > The implementation provides a revocable attachment mechanism using > dma-buf move operations. MMIO regions are normally pinned as BARs > don't change physical addresses, but access is revoked when the VFIO > device is closed or a PCI reset is issued. This ensures kernel > self-defense against potentially hostile userspace. This still completely fails to explain why you think that it actually is safe without the proper pgmap handling.