+ mm-damon-reclaim-use-parameter-context-correctly.patch added to mm-new branch

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

The patch titled
     Subject: mm/damon/reclaim: use parameter context correctly
has been added to the -mm mm-new branch.  Its filename is
     mm-damon-reclaim-use-parameter-context-correctly.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-damon-reclaim-use-parameter-context-correctly.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: SeongJae Park <sj@kernel.org>
Subject: mm/damon/reclaim: use parameter context correctly
Date: Sun, 6 Jul 2025 12:32:07 -0700

damon_reclaim_apply_parameters() allocates a new DAMON context, stages
user-specified DAMON parameters on it, and commits to running DAMON
context at once, using damon_commit_ctx().  The code is mistakenly
over-writing the monitoring attributes and the reclaim scheme on the
running context.  It is not causing a real problem for monitoring
attributes, but the scheme overwriting can remove scheme's internal status
such as charged quota.  Fix the wrong use of the parameter context.

Link: https://lkml.kernel.org/r/20250706193207.39810-7-sj@kernel.org
Fixes: 11ddcfc257a3 ("mm/damon/reclaim: use damon_commit_ctx()")
Signed-off-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/damon/reclaim.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/damon/reclaim.c~mm-damon-reclaim-use-parameter-context-correctly
+++ a/mm/damon/reclaim.c
@@ -194,7 +194,7 @@ static int damon_reclaim_apply_parameter
 	if (err)
 		return err;
 
-	err = damon_set_attrs(ctx, &damon_reclaim_mon_attrs);
+	err = damon_set_attrs(param_ctx, &damon_reclaim_mon_attrs);
 	if (err)
 		goto out;
 
@@ -202,7 +202,7 @@ static int damon_reclaim_apply_parameter
 	scheme = damon_reclaim_new_scheme();
 	if (!scheme)
 		goto out;
-	damon_set_schemes(ctx, &scheme, 1);
+	damon_set_schemes(param_ctx, &scheme, 1);
 
 	if (quota_mem_pressure_us) {
 		goal = damos_new_quota_goal(DAMOS_QUOTA_SOME_MEM_PSI_US,
_

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

mm-damon-core-handle-damon_call_control-as-normal-under-kdmond-deactivation.patch
mm-damon-introduce-damon_stat-module.patch
mm-damon-introduce-damon_stat-module-fix.patch
mm-damon-stat-calculate-and-expose-estimated-memory-bandwidth.patch
mm-damon-stat-calculate-and-expose-idle-time-percentiles.patch
docs-admin-guide-mm-damon-add-damon_stat-usage-document.patch
mm-damon-paddr-use-alloc_migartion_target-with-no-migration-fallback-nodemask.patch
revert-mm-rename-alloc_demote_folio-to-alloc_migrate_folio.patch
revert-mm-make-alloc_demote_folio-externally-invokable-for-migration.patch
selftets-damon-add-a-test-for-memcg_path-leak.patch
mm-damon-sysfs-schemes-decouple-from-damos_quota_goal_metric.patch
mm-damon-sysfs-schemes-decouple-from-damos_action.patch
mm-damon-sysfs-schemes-decouple-from-damos_wmark_metric.patch
mm-damon-sysfs-schemes-decouple-from-damos_filter_type.patch
mm-damon-sysfs-decouple-from-damon_ops_id.patch
selftests-damon-add-drgn-script-for-extracting-damon-status.patch
selftests-damon-_damon_sysfs-set-kdamondpid-in-start.patch
selftests-damon-add-python-and-drgn-based-damon-sysfs-test.patch
selftests-damon-sysfspy-test-monitoring-attribute-parameters.patch
selftests-damon-sysfspy-test-adaptive-targets-parameter.patch
selftests-damon-sysfspy-test-damos-schemes-parameters-setup.patch
mm-damon-add-trace-event-for-auto-tuned-monitoring-intervals.patch
mm-damon-add-trace-event-for-effective-size-quota.patch
samples-damon-wsse-fix-boot-time-enable-handling.patch
samples-damon-prcl-fix-boot-time-enable-crash.patch
samples-damon-mtier-support-boot-time-enable-setup.patch
mm-damon-reclaim-reset-enabled-when-damon-start-failed.patch
mm-damon-lru_sort-reset-enabled-when-damon-start-failed.patch
mm-damon-reclaim-use-parameter-context-correctly.patch