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charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: A89F3C000B X-Rspam-User: X-Stat-Signature: a77swocu57greuzshkojz43dc4j3ct5g X-HE-Tag: 1768829452-287887 X-HE-Meta: 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 nWn5IhuV ny1docAPbbB/7nuYr/tI3XTynO9mhKaUq+DQIHxhWKK1BbF/+ieQmxr8FJvHUhQlf+MzTRgehFjQ5t6EpWt6JpHvcSoQGAB4CFkUWEvXnJ4t53UozH6iMiaeceXlbAJHU/4fSAd/sJAUKdYMub3pEiVpg4AdxACVEMl0/+WkmYrqTS+3gbMUjnhZZp2/YPTuDKJNtEltazGATwbQrK56Iw5Zijg== 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 19/01/2026 12:09, David Hildenbrand (Red Hat) wrote: > On 1/7/26 17:48, 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. > > Yes, I assume so. Using FORCE_READ() etc is the way to go. > > > Should we add > > Fixes: 46036188ea1f ("selftests/mm: build with -O2")  Yes that seems reasonable, the test was arguably broken to start with but it is this commit that revealed it ;) - Kevin