On Thu, Jun 11, 2026 at 10:09 AM David Hildenbrand (Arm) <[email protected]> wrote: > > On 6/11/26 17:58, Nico Pache wrote: > > Hi, > > > > While testing my mTHP code I noticed that mm selftests caused an accounting > > error in > > /sys/kernel/mm/transparent_hugepage/hugepages-2048kB/stats/nr_anon > > > > At first I thought I might have caused a regression, but when retesting > > with 7.1-rc5 (without my code), the issue was still present. > > > > This issue occurs in two mm selftests: > > 1) hmm test > > 2) migration - private_anon_htlb test > > > > I spoke to David about this and he suggested the following diff which seems > > to have solved both issues. > > > > David would you like to send a formal patch or patches? > > > > Cheers, > > -- Nico > > > > Diff for (1) > > > > diff --git a/mm/memremap.c b/mm/memremap.c > > index 053842d45cb1..683a77dd679d 100644 > > --- a/mm/memremap.c > > +++ b/mm/memremap.c > > @@ -425,6 +425,7 @@ void free_zone_device_folio(struct folio *folio) > > mem_cgroup_uncharge(folio); > > > > if (folio_test_anon(folio)) { > > + mod_mthp_stat(folio_order(folio), MTHP_STAT_NR_ANON, -1); > > for (i = 0; i < nr; i++) > > __ClearPageAnonExclusive(folio_page(folio, i)); > > } > > Wasn't there another issue with hugetlb? > > diff --git a/mm/migrate.c b/mm/migrate.c > index 8a64291ab5b4..0aec894266f2 100644 > --- a/mm/migrate.c > +++ b/mm/migrate.c > @@ -590,7 +590,8 @@ static int __folio_migrate_mapping(struct address_space > *mapping, > /* No turning back from here */ > newfolio->index = folio->index; > newfolio->mapping = folio->mapping; > - if (folio_test_anon(folio) && folio_test_large(folio)) > + if (folio_test_anon(folio) && folio_test_large(folio) && > + !folio_test_hugetlb(folio)) > mod_mthp_stat(folio_order(folio), MTHP_STAT_NR_ANON, > 1); > if (folio_test_swapbacked(folio)) > __folio_set_swapbacked(newfolio); > @@ -623,7 +624,8 @@ static int __folio_migrate_mapping(struct address_space > *mapping, > */ > newfolio->index = folio->index; > newfolio->mapping = folio->mapping; > - if (folio_test_anon(folio) && folio_test_large(folio)) > + if (folio_test_anon(folio) && folio_test_large(folio) && > + !folio_test_hugetlb(folio)) > mod_mthp_stat(folio_order(folio), MTHP_STAT_NR_ANON, 1); > folio_ref_add(newfolio, nr); /* add cache reference */ > if (folio_test_swapbacked(folio)) > > > Yeah, if you have some capacity, please send patches (and figure out Fixes:) > :)
Yeah ill spend some time next week trying to understand why these are happening and produce patches :) > > > -- > Cheers, > > David >
