From: Li Liguang liliguang@baidu.com

Kswapd will reclaim memory when memory pressure is high, the annonymous memory will be compressed and stored in the zpool if zswap is enabled. The memcg_kmem_bypass() in get_obj_cgroup_from_page() will bypass the kernel thread and cause the compressed memory not charged to its memory cgroup.

Remove the memcg_kmem_bypass() and properly charge compressed memory to its corresponding memory cgroup.

Link: https://lore.kernel.org/linux-mm/CALvZod4nnn8BHYqAM4xtcR0Ddo2-Wr8uKm9h_CHWUa... Fixes: f4840ccfca25 ("zswap: memcg accounting") Cc: stable@vger.kernel.org # 5.19+ Acked-by: Shakeel Butt shakeelb@google.com Acked-by: Shakeel Butt shakeelb@google.com Reviewed-by: Muchun Song songmuchun@bytedance.com Signed-off-by: Li Liguang liliguang@baidu.com Signed-off-by: Johannes Weiner hannes@cmpxchg.org --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

This fell through the cracks in summer as it didn't make it to the right mailing lists. Resending.

I know it's close to 6.1-final, but the fix should be safe to put in. It's straight-forward and obvious code-wise. We also have large parts of production running on it without problems.

diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 2d8549ae1b30..a1a35c12635e 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3026,7 +3026,7 @@ struct obj_cgroup *get_obj_cgroup_from_page(struct page *page) { struct obj_cgroup *objcg;

- if (!memcg_kmem_enabled() || memcg_kmem_bypass()) + if (!memcg_kmem_enabled()) return NULL;

if (PageMemcgKmem(page)) {