#regzbot introduced: 7460b470a131f985a70302a322617121efdd7caa

Hey folks,

We discovered madvise(MADV_REMOVE) on a 4KiB range within a huge-page-backed MAP_SHARED memfd region corrupts nearby pages.

Using the reproducible test in https://github.com/dfinity/thp-madv-remove-test this was bisected to the first bad commit:

commit 7460b470a131f985a70302a322617121efdd7caa
Author: Zi Yan <ziy@nvidia.com>
Date: Fri Mar 7 12:40:00 2025 -0500

mm/truncate: use folio_split() in truncate operation

v7.0-rc1 still has the regression.

The repo mentioned above explains how to reproduce the regression and contains the necessary logs of failed runs on 7460b470a131 and v7.0-rc1, as well as a successful run on its parent 4b94c18d1519.

Best regards,

Bas van Dijk

DFINITY Foundation