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Without it, the child will be able > to write to parent's pages when mapped as PROT_READ|PROT_WRITE and MAP_PRIVATE, > which will cause data corruption in the parent process. > > This issue can also be exposed by "memfd_test hugetlbfs" kselftest (if it can > pass the F_SEAL_FUTURE_WRITE test first, though). > > Signed-off-by: Peter Xu > --- > mm/hugetlb.c | 2 ++ > 1 file changed, 2 insertions(+) Reviewed-by: Mike Kravetz I think we need to add, "Fixes: 4eae4efa2c29" as this is now in v5.12 -- Mike Kravetz