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charset="UTF-8" X-Rspamd-Queue-Id: B296A40011 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: x3rnzc4b45rsgcgw6btgcuwqpdtwhrx1 X-HE-Tag: 1672883493-909337 X-HE-Meta: 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 npu3dl0i s/idLO3y3vS9GPfTjYPjnDQFLEcJPOfct44oiZbYdnAERI1LFkMFbBEfpDPSizDmylHFaN9+QSj7KOzCnJKsIoSp12w== 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 Wed, Jan 4, 2023 at 10:52 PM Peter Xu wrote: > > Switch to use type "long" for page accountings and retval across the whole > procedure of change_protection(). > > The change should have shrinked the possible maximum page number to be half > comparing to previous (ULONG_MAX / 2), but it shouldn't overflow on any > system either because the maximum possible pages touched by change > protection should be ULONG_MAX / PAGE_SIZE. > > Two reasons to switch from "unsigned long" to "long": > > 1. It suites better on count_vm_numa_events(), whose 2nd parameter takes > a long type. > > 2. It paves way for returning negative (error) values in the future. > > Currently the only caller that consumes this retval is change_prot_numa(), > where the unsigned long was converted to an int. Since at it, touching up > the numa code to also take a long, so it'll avoid any possible overflow too > during the int-size convertion. > > Signed-off-by: Peter Xu > --- > include/linux/hugetlb.h | 4 ++-- > include/linux/mm.h | 2 +- > mm/hugetlb.c | 4 ++-- > mm/mempolicy.c | 2 +- > mm/mprotect.c | 26 +++++++++++++------------- > 5 files changed, 19 insertions(+), 19 deletions(-) Acked-by: James Houghton