+ mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity.patch added to mm-hotfixes-unstable branch

+ mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm/damon/core: make charge_addr_from aware of end-address exclusivity
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: SeongJae Park <sj@kernel.org>
Subject: mm/damon/core: make charge_addr_from aware of end-address exclusivity
Date: Mon, 27 Apr 2026 21:29:40 -0700

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>
---

 mm/damon/core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/damon/core.c~mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity
+++ a/mm/damon/core.c
@@ -2106,7 +2106,7 @@ static void damos_apply_scheme(struct da
 		if (damos_quota_is_set(quota) &&
 				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)
_

Patches currently in -mm which might be from sj@kernel.org are

mm-damon-sysfs-schemes-call-missing-mem_cgroup_iter_break.patch
mm-damon-fix-damos_stat-tracepoint-format-for-sz_applied.patch
mm-damon-core-make-charge_addr_from-aware-of-end-address-exclusivity.patch
docs-mm-damon-maintainer-profile-add-ai-review-usage-guideline.patch
mm-damon-core-introduce-damon_ctx-paused.patch
mm-damon-sysfs-add-pause-file-under-context-dir.patch
docs-mm-damon-design-update-for-context-pause-resume-feature.patch
docs-admin-guide-mm-damon-usage-update-for-pause-file.patch
docs-abi-damon-update-for-pause-sysfs-file.patch
mm-damon-tests-core-kunit-test-pause-commitment.patch
selftests-damon-_damon_sysfs-support-pause-file-staging.patch
selftests-damon-drgn_dump_damon_status-dump-pause.patch
selftests-damon-sysfspy-check-pause-on-assert_ctx_committed.patch
selftests-damon-sysfspy-pause-damon-before-dumping-status.patch