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From: SJ Park <sj@kernel.org>
Cc: SJ Park <sj@kernel.org>, "# 5 . 15 . x" <stable@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Brendan Higgins <brendan.higgins@linux.dev>,
	David Gow <davidgow@davidgow.net>,
	Fernand Sieber <sieberf@amazon.com>,
	Leonard Foerster <foersleo@amazon.de>,
	SeongJae Park <sjpark@amazon.de>,
	Shakeel Butt <shakeel.butt@linux.dev>,
	damon@lists.linux.dev, kunit-dev@googlegroups.com,
	linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
	linux-mm@kvack.org
Subject: [RFC PATCH 0/5] mm/damon: unurgent fixes for infinite loop, NULL de-ref and races
Date: Sat, 11 Jul 2026 11:04:03 -0700	[thread overview]
Message-ID: <20260711180409.82093-1-sj@kernel.org> (raw)

Sashiko found a few issues in DAMON that could cause infinite loop, NULL
dereference and monitoring results degradation.  The first two sounds
scary but the infinite loop happens only under unreasonable user setup.
The NULL dereference is only in a unit test.  Monitoring results
degradation is trivial since it is only best-effort, and those happens
from only unlikely races.  Still those are bugs that better to fix if
possible. Fix those.

SJ Park (5):
  mm/damon/core: avoid infinite kdamond_merge_regions() internal loop
  mm/damon/tests/core-kunit: catch test failure in
    test_merge_regions_of()
  mm/damon/vaddr: drop last same folio access check optimization
  mm/damon/paddr: drop last same folio access check reuse optimization
  mm/damon/sysfs: read ops_id only once

 mm/damon/core.c             | 13 +++++++++----
 mm/damon/paddr.c            | 20 ++++----------------
 mm/damon/sysfs.c            |  6 ++++--
 mm/damon/tests/core-kunit.h |  3 +++
 mm/damon/vaddr.c            | 26 ++++----------------------
 5 files changed, 24 insertions(+), 44 deletions(-)


base-commit: 65b3b6001701d46d5360097bdc90dfa1c06a1239
-- 
2.47.3

             reply	other threads:[~2026-07-11 18:04 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-11 18:04 SJ Park [this message]
2026-07-11 18:04 ` [RFC PATCH 1/5] mm/damon/core: avoid infinite kdamond_merge_regions() internal loop SJ Park
2026-07-11 18:04 ` [RFC PATCH 2/5] mm/damon/tests/core-kunit: catch test failure in test_merge_regions_of() SJ Park
2026-07-11 18:04 ` [RFC PATCH 3/5] mm/damon/vaddr: drop last same folio access check optimization SJ Park
2026-07-11 18:04 ` [RFC PATCH 4/5] mm/damon/paddr: drop last same folio access check reuse optimization SJ Park
2026-07-11 18:04 ` [RFC PATCH 5/5] mm/damon/sysfs: read ops_id only once SJ Park

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