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charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.56.2 (3.56.2-2.fc42) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Wed, 2026-07-01 at 18:33 +0200, David Hildenbrand (Arm) wrote: >=20 > There is some grammatical issue that makes me wonder whether you are > talking > about the present or the past. > >=20 Changelog issues fixed for v2. Thank you. > > Reproduced by syzkaller: hwpoison-inject a few subpages of a large > > shmem > > folio, then MADV_REMOVE (fallocate punch hole) on the same range, > > which > > splits the partial folio to a non-zero order. >=20 > As Lance says, after we do the TestSetPageHWPoison() in > memory_failure(), we > call try_to_split_thp_page(). Does that already suffice, even without > the > MADV_REMOCE. While fa5a06170036 was created to deal with having the folio split to >0 order, in this case it looks like the try_to_split_thp_page() call from memory_failure() failed, presumably because folio_ref_freeze() could not=C2=A0 freeze the order 7 folio, because the reproducer had=C2=A0 multiple threads poking at that folio simultaneously. This test case is rather contrived, like most syzkaller tests, but given that the try_to_split_thp_page() call could fail for various reasons, we do need this fallback path. --=20 All Rights Reversed.