[PATCH 6.1.y] mm/damon/core: make charge_addr_from aware of end-address exclusivity

[SJ Park <sj@kernel.org>]

From: SeongJae Park <sj@kernel.org>

DAMON region end address is exclusive one, but charge_addr_from is
assigned assuming the end address is inclusive.  As a result, DAMOS action
to next up to min_region_sz memory can be skipped.  This is quite
negligible user impact.  But, the bug is a bug that can be very simply
fixed.  Fix the wrong assignment to respect the exclusiveness of the
address.

The issue was discovered [1] by Sashiko.

Link: https://lore.kernel.org/20260428042942.118230-1-sj@kernel.org
Link: https://lore.kernel.org/20260428032324.115663-1-sj@kernel.org [1]
Fixes: 50585192bc2e ("mm/damon/schemes: skip already charged targets and regions")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: <stable@vger.kernel.org> # 5.16.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 5a2d162e22bf33eb89d53e802d0fc1ec422e19b6)
Signed-off-by: SJ Park <sj@kernel.org>
---
 mm/damon/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/damon/core.c b/mm/damon/core.c
index d293200d824e9..4b434ebd37c53 100644
--- a/mm/damon/core.c
+++ b/mm/damon/core.c
@@ -803,7 +803,7 @@ static void damon_do_apply_schemes(struct damon_ctx *c,
 			quota->charged_sz += sz;
 			if (quota->esz && quota->charged_sz >= quota->esz) {
 				quota->charge_target_from = t;
-				quota->charge_addr_from = r->ar.end + 1;
+				quota->charge_addr_from = r->ar.end;
 			}
 		}
 		if (s->action != DAMOS_STAT)
-- 
2.47.3