+ selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch added to mm-unstable branch

+ selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: selftest/damon: add a test for duplicate context dirs creation
has been added to the -mm mm-unstable branch.  Its filename is
     selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch

This patch will later appear in the mm-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: selftest/damon: add a test for duplicate context dirs creation
Date: Fri, 9 Sep 2022 20:28:55 +0000

Patch series "mm/damon: minor fixes and cleanups".

This patchset contains minor fixes and cleanups for DAMON including

- selftest for a bug we found before (Patch 1), 
- fix of region holes in vaddr corner case and a kunit test for it
  (Patches 2 and 3), and
- documents/Kconfig updates for title wordsmithing (Patch 4) and more
  aggressive DAMON debugfs interface deprecation announcement
  (Patches 5-7).


This patch (of 7):

Commit d26f60703606 ("mm/damon/dbgfs: avoid duplicate context directory
creation") fixes a bug which could result in memory leak and DAMON
disablement.  This commit adds a selftest for verifying the fix and avoid
regression.

Link: https://lkml.kernel.org/r/20220909202901.57977-1-sj@kernel.org
Link: https://lkml.kernel.org/r/20220909202901.57977-2-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendanhiggins@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Yun Levi <ppbuk5246@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/damon/Makefile                              |    1 
 tools/testing/selftests/damon/debugfs_duplicate_context_creation.sh |   27 ++++++++++
 2 files changed, 28 insertions(+)

--- /dev/null
+++ a/tools/testing/selftests/damon/debugfs_duplicate_context_creation.sh
@@ -0,0 +1,27 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+source _debugfs_common.sh
+
+# Test duplicated context creation
+# ================================
+
+if ! echo foo > "$DBGFS/mk_contexts"
+then
+	echo "context creation failed"
+	exit 1
+fi
+
+if echo foo > "$DBGFS/mk_contexts"
+then
+	echo "duplicate context creation success"
+	exit 1
+fi
+
+if ! echo foo > "$DBGFS/rm_contexts"
+then
+	echo "context deletion failed"
+	exit 1
+fi
+
+exit 0
--- a/tools/testing/selftests/damon/Makefile~selftest-damon-add-a-test-for-duplicate-context-dirs-creation
+++ a/tools/testing/selftests/damon/Makefile
@@ -6,6 +6,7 @@ TEST_GEN_FILES += huge_count_read_write
 TEST_FILES = _chk_dependency.sh _debugfs_common.sh
 TEST_PROGS = debugfs_attrs.sh debugfs_schemes.sh debugfs_target_ids.sh
 TEST_PROGS += debugfs_empty_targets.sh debugfs_huge_count_read_write.sh
+TEST_PROGS += debugfs_duplicate_context_creation.sh
 TEST_PROGS += sysfs.sh
 
 include ../lib.mk
_

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

mm-demotion-update-node_is_toptier-to-work-with-memory-tiers-fix.patch
selftest-damon-add-a-test-for-duplicate-context-dirs-creation.patch
mm-damon-core-avoid-holes-in-newly-set-monitoring-target-ranges.patch
mm-damon-core-test-test-damon_set_regions.patch
docs-admin-guide-mm-damon-rename-the-title-of-the-document.patch
mm-damon-kconfig-notify-debugfs-deprecation-plan.patch
docs-admin-guide-mm-damon-start-mention-the-dependency-as-sysfs-instead-of-debugfs.patch
docs-admin-guide-mm-damon-usage-note-damon-debugfs-interface-deprecation-plan.patch