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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam12 X-Stat-Signature: 4um48nnjiidqu4dudxkgwhe7awefbgie X-Rspamd-Queue-Id: 92E9C40008 X-Rspam-User: X-HE-Tag: 1769103792-458368 X-HE-Meta: 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 ZOGbwix6 k5RTPfrHvwc9zE034mfh4Ny5vohBna0x3JYIWbLJt9pjAYEDT0I9inc8FnDVoHHPXZKEcCQ+/l27StmmbhXhpek/1vg443Ri2P5Ur7yZrIs8tKAMhun77fYbKUXG2rkFi4XlsJ2NOYKcCdqPPgb90145kYVdS0qdY2N4lfOrIFzMk9s7mlhmzfeP+nV3ml+npiUOaJySPO6Z3rlkxdPu0Bk1O/uZuBFBYkQa8ur4wBDgpQmMFQlXj/tj5p9ohQjHUSEZOjLTmHGoTpeY= 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 22/01/2026 5:02 pm, Kevin Brodsky wrote: > One of the pagemap_ioctl tests attempts to fault in pages by > memcpy()'ing them to an unused buffer. This probably worked > originally, but since commit 46036188ea1f ("selftests/mm: build with > -O2") the compiler is free to optimise away that unused buffer and > the memcpy() with it. As a result there might not be any resident > page in the mapping and the test may fail. > > We don't need to copy all that memory anyway. Just fault in every > page. > > While at it also make sure to compute the number of pages once using > simple integer arithmetic instead of ceilf() and implicit > conversions. > > Fixes: 46036188ea1f ("selftests/mm: build with -O2") > Cc: Usama Anjum > Acked-by: David Hildenbrand (Red Hat) > Reviewed-by: Dev Jain > Signed-off-by: Kevin Brodsky > --- Reviewed-by: Muhammad Usama Anjum