+ mm-damon-core-avoid-destroyed-target-reference-from-damos-quota.patch added to mm-new branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: mm/damon/core: avoid destroyed target reference from DAMOS quota
has been added to the -mm mm-new branch.  Its filename is
     mm-damon-core-avoid-destroyed-target-reference-from-damos-quota.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-avoid-destroyed-target-reference-from-damos-quota.patch

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

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patches, and acceptance into mm-new is a notification for others take
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------------------------------------------------------
From: Akinobu Mita <akinobu.mita@gmail.com>
Subject: mm/damon/core: avoid destroyed target reference from DAMOS quota
Date: Sat, 17 May 2025 23:18:52 +0900

When the number of the monitoring targets in running contexts is reduced,
there may be DAMOS quotas referencing the targets that will be destroyed.

Applying the scheme action for such DAMOS scheme will be skipped forever
looking for the starting part of the region for the destroyed monitoring
target.

To fix this issue, when the monitoring target is destroyed, reset the
starting part for all DAMOS quotas that reference the target.

Link: https://lkml.kernel.org/r/20250517141852.142802-1-akinobu.mita@gmail.com
Fixes: da87878010e5 ("mm/damon/sysfs: support online inputs update")
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Reviewed-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/core.c |    8 ++++++++
 1 file changed, 8 insertions(+)

--- a/mm/damon/core.c~mm-damon-core-avoid-destroyed-target-reference-from-damos-quota
+++ a/mm/damon/core.c
@@ -1093,9 +1093,17 @@ static int damon_commit_targets(
 			if (err)
 				return err;
 		} else {
+			struct damos *s;
+
 			if (damon_target_has_pid(dst))
 				put_pid(dst_target->pid);
 			damon_destroy_target(dst_target);
+			damon_for_each_scheme(s, dst) {
+				if (s->quota.charge_target_from == dst_target) {
+					s->quota.charge_target_from = NULL;
+					s->quota.charge_addr_from = 0;
+				}
+			}
 		}
 	}
 
_

Patches currently in -mm which might be from akinobu.mita@gmail.com are

mm-damon-core-avoid-destroyed-target-reference-from-damos-quota.patch