Hello,

pgdat_page_ext_init() has no effect on FLATMEM. The pgdat is always
the zero-initialized contig_page_data, because no architecture
supports FLATMEM + NUMA.

That constraint is only implicit in the arch Kconfig files. So patch 1
makes it explicit in mm/Kconfig, and patch 2 removes pgdat_page_ext_init().

No functional change.

---
Changes from v1 [1]
- Add patch 1 to make FLATMEM depend on !NUMA

[1] https://lore.kernel.org/all/20260803134822.2568766-1-ekffu200098@gmail.com/ 
---

Sang-Heon Jeon (2):
  mm/Kconfig: make FLATMEM depend on !NUMA
  mm/page_ext: remove pgdat_page_ext_init()

 include/linux/page_ext.h | 5 -----
 mm/Kconfig               | 2 ++
 mm/mm_init.c             | 1 -
 mm/page_ext.c            | 9 ---------
 4 files changed, 2 insertions(+), 15 deletions(-)

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2.43.0