[PATCH 1/3] mm/damon/paddr: use do_div() on i386 for damon_pa_pageout() return value

[SeongJae Park]

Otherwise, __udidi3 linking problem happens on certain configs.

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-kbuild-all/202508241831.EKwdwXZL-lkp@xxxxxxxxx/
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
 mm/damon/paddr.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/mm/damon/paddr.c b/mm/damon/paddr.c
index 5fad2f9a99a0..09c87583af6c 100644
--- a/mm/damon/paddr.c
+++ b/mm/damon/paddr.c
@@ -135,6 +135,18 @@ static bool damon_pa_invalid_damos_folio(struct folio *folio, struct damos *s)
 	return false;
 }
 
+/* convert physical address to core-layer address */
+static unsigned long damon_pa_core_addr(phys_addr_t pa,
+		unsigned long addr_unit)
+{
+#ifdef __i386__
+	do_div(pa, addr_unit);
+	return pa;
+#else
+	return pa / addr_unit;
+#endif
+}
+
 static unsigned long damon_pa_pageout(struct damon_region *r,
 		unsigned long addr_unit, struct damos *s,
 		unsigned long *sz_filter_passed)
@@ -190,7 +202,7 @@ static unsigned long damon_pa_pageout(struct damon_region *r,
 	applied = reclaim_pages(&folio_list);
 	cond_resched();
 	s->last_applied = folio;
-	return applied * PAGE_SIZE / addr_unit;
+	return damon_pa_core_addr(applied * PAGE_SIZE, addr_unit);
 }
 
 static inline unsigned long damon_pa_mark_accessed_or_deactivate(
-- 
2.39.5