mm: memcontrol: add VM_BUG_ON_FOLIO() to catch lru folio in mem_cgroup_migrate()

mem_cgroup_migrate() will clear the memcg data of the old folio,
therefore, the callers must make sure the old folio is no longer on the
LRU list, otherwise the old folio can not get the correct lruvec object
without the memcg data, which could lead to potential problems [1].

Thus adding a VM_BUG_ON_FOLIO() to catch this issue.

[1] https://lore.kernel.org/all/5ab860d8ee987955e917748f9d6da525d3b52690.1718326003.git.baolin.wang@linux.alibaba.com/

Link: https://lkml.kernel.org/r/66d181c41b7ced35dbd39ffd3f5774a11aef266a.1718327124.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Suggested-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Baolin Wang 2024-06-14 09:07:42 +08:00 committed by Andrew Morton
parent 83d0d46a80
commit a6ab9c82d3

View File

@ -7807,6 +7807,7 @@ void mem_cgroup_migrate(struct folio *old, struct folio *new)
VM_BUG_ON_FOLIO(!folio_test_locked(new), new);
VM_BUG_ON_FOLIO(folio_test_anon(old) != folio_test_anon(new), new);
VM_BUG_ON_FOLIO(folio_nr_pages(old) != folio_nr_pages(new), new);
VM_BUG_ON_FOLIO(folio_test_lru(old), old);
if (mem_cgroup_disabled())
return;