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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: fiuehh4zt1m1opoyja4hxochdsxt686u X-Rspamd-Queue-Id: 7F6E940015 X-HE-Tag: 1674306628-479804 X-HE-Meta: U2FsdGVkX19oD2pohEI67QtaqRvaOLSOeG+PVKWjzm+skLgWWT+SR5nZ3IrwWwJqIKf6jzrGCEfIoeyoMnQbE3obkALR8hKN/mGY5eM8paHPcn6IFRH/JQQwo9o43ZeTXZSL9tPrnNZ6k7OA6Sa/PjedR4PdA8TfUEpaO3eFm7nA/fxixxw4yKKooLtwZ70E8pJ8ikWuSfy0y2ETb8+9EBjTobZC3wr4KOuYN/YYQEZP8ZAsYAuusrbKbDS/SDGcgYFvgUqq/FiQvsQt1osIRCT829rvC0NjtkK5FKl0n1ocqbcwUZj9mHnMWvFAjDKQFcM/+6hi2+Wtx1jU8pLUCEr+TJri+iyjTSb82S55ojy44t7uucIHaMVlsV9KWGWMItq8j8GiQGDik2ysguW+xQhbZaoVNFd0S/C5AM4GZOGdvYMu/YqyDoRQyvFTyZoTgznhGf0Dpp09RxXi8rbEaAe8LncLDpjGfNzhuP31eF5uKUJEnLU/OCiid2UEr9z5+HDnZXI2F/qwCazy4Jq/b/kyob1u5WceQ0MYi+dmPNQBi22JbQzgbch9FAR/CiGANrqCNLafkuaEJQYu0WfxFtWfKOIW+Corh7vxVo3rUCfz3kn8VAtywlz+oK3+KCaDE0PXj2nzbVotlb2SicR0t5fHlC2q9OhhhyWJDhT3xNpZvxF/ShSNSg5yvJHA/a0Td3fbA31gl6ue4vCiqfpt5MbFUr1yv2FEVyEtNTbBJ3vfpW5sKU57Us96nrWly6WQm1hSRis1dQZ2mCCeGiqQBZ/OhQCSBTzvQTmnNHVjPR2pms5u+KEUXgCf6gXqJ9RtkXJmT2tgoqe/IIfaRPf+zL3kyb7GMSKSJPnBL/W9MdlOG4zmLTcxm0ZfVBYlBIuVdJcMvc3CVSl5DnePVc41pTCx7PfMKDUt0jNq67xoJgVX746NrV6D73DHpl2c/jKTUoVrQW+G9YeLcV4bgSF XWVrUAfk 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 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 Fri, Jan 20, 2023 at 05:55:50PM +0000, David Howells wrote: > (3) Any other sort of iterator. > > No refs or pins are obtained on the page, the assumption is made that > the caller will manage page retention. ITER_ALLOW_P2PDMA is not > permitted. The ITER_ALLOW_P2PDMA check here is fundamentally wrong and will break things like io_uring to fixed buffers on NVMe. ITER_ALLOW_P2PDMA should strictly increase the group of acceptable iters, it does must not restrict anything.