Hi,
Thanks for your patch.
FYI: kernel test robot notices the stable kernel rule is not satisfied.
Rule: 'Cc: stable@vger.kernel.org' or 'commit <sha1> upstream.' Subject: [PATCH v2 stable-4.19 1/3] mm/page_alloc: use ac->high_zoneidx for classzone_idx Link: https://lore.kernel.org/stable/20220925103529.13716-2-yongw.pur%40gmail.com
The check is based on https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html