linux.git/include/linux/damon.h, branch master

MAINTAINERS: s/SeongJae/SJ/

2026-07-09T22:48:53Z

My legal and preferred first names are SeongJae and SJ, respectively. I was using the legal name for commits and tags, while using the preferred name for conversations. It sometimes confuses people including myself. Consistently use the preferred name. Together remove copyright notes on files. Those are only confusing for people who are not familiar with the law. Meanwhile, we can infer the information in a better way from git logs and public information. Link: https://lore.kernel.org/20260630013820.143366-1-sj@kernel.org Signed-off-by: SJ Park Acked-by: Lorenzo Stoakes Acked-by: David Hildenbrand (Arm) Cc: Liam R. Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm/damon: add a kernel-doc comment for damon_ctx->rnd_state

2026-07-02T02:02:55Z

Fix below kernel document build warning: WARNING: ../include/linux/damon.h:909 struct member 'rnd_state' not described in 'damon_ctx' Link: https://lore.kernel.org/20260628220808.98931-3-sj@kernel.org Fixes: 9012c4e647df ("mm/damon: replace damon_rand() with a per-ctx lockless PRNG") Signed-off-by: SJ Park Reported-by: Randy Dunlap Closes: https://lore.kernel.org/4df95955-b255-4e5a-90c4-35db02f3111f@infradead.org Signed-off-by: Andrew Morton

mm/damon: add a kernel-doc comment for damon_ctx->probes

2026-07-02T02:02:55Z

The two fields of damon_ctx struct dont have their kernel-doc comments. That causes kernel document builds to warn. Fix those. This patch (of 2): Fix below document build warning: WARNING: ../include/linux/damon.h:909 struct member 'probes' not described in 'damon_ctx' Link: https://lore.kernel.org/20260628220808.98931-1-sj@kernel.org Link: https://lore.kernel.org/20260628220808.98931-2-sj@kernel.org Fixes: 18c777859f28 ("mm/damon/core: embed damon_probe objects in damon_ctx") Signed-off-by: SJ Park Reported-by: Randy Dunlap Closes: https://lore.kernel.org/4df95955-b255-4e5a-90c4-35db02f3111f@infradead.org Signed-off-by: Andrew Morton

mm/damon/ops-common: handle extreme intervals in damon_hot_score()

2026-07-02T02:02:53Z

Fix three issues in damon_hot_score() that comes from wrong handling of extreme (zero or too high) monitoring intervals user setup. When the user sets sampling interval zero, damon_max_nr_accesses(), which is called from damon_hot_score(), causes a divide-by-zero. Needless to say, it is a problem. When the user sets the aggregation interval zero, the function returns zero. It is wrong, since the real maximum nr_acceses in the setup should be one. Worse yet, it can cause another divide-by-zero from its caller, damon_hot_score(), since it uses damon_max_nr_accesses() return value as a denominator. When the user sets the aggregation interval very high, damon_hot_score() could return a value out of [0, DAMOS_MAX_SCORE] range. Since the return value is used as an index to the regions_score_histogram array, which is DAMOS_MAX_SCORE+1 size, it causes out of bounds array access. The issues can be relatively easily reproduced like below. The sysfs write permission is required, though. # ./damo start --damos_action lru_prio --damos_quota_space 100M \ --damos_quota_interval 1s # cd /sys/kernel/mm/damon/admin/kdamonds/0 # echo 0 > contexts/0/monitoring_attrs/intervals/sample_us # echo 0 > contexts/0/monitoring_attrs/intervals/aggr_us # echo commit > state # dmesg [...] [ 131.329762] Oops: divide error: 0000 [#1] SMP NOPTI [...] [ 131.336089] RIP: 0010:damon_hot_score+0x27/0xd0 [...] Fix the divide-by-zero intervals problems by explicitly handling the zero intervals in damon_max_nr_accesses(). Fix the out-of-bound array access by applying [0, DAMOS_MAX_SCORE] bounds before returning from damon_hot_score(). The issue was discovered [1] by Sashiko. Link: https://lore.kernel.org/20260623135834.67189-1-sj@kernel.org Link: https://lore.kernel.org/20260619202459.145010-1-sj@kernel.org [1] Fixes: 198f0f4c58b9 ("mm/damon/vaddr,paddr: support pageout prioritization") Signed-off-by: SeongJae Park Cc: # 5.16.x Signed-off-by: Andrew Morton

mm/damon: fix missing parens in macro arguments

2026-06-04T21:45:02Z

Patch series "mm/damon: fix macro arguments and clarify quota goals doc", v2. This patch (of 2): The DAMON iterator macros do not wrap their pointer arguments with parentheses. This can cause build failures when the argument is a complex expression due to operator precedence issues. Add missing parentheses around the arguments in the following macros to prevent potential build failures: - damon_for_each_region() - damon_for_each_region_from() - damon_for_each_region_safe() - damos_for_each_quota_goal() Link: https://lore.kernel.org/20260521202020.126500-1-maksym.shcherba@lnu.edu.ua Link: https://lore.kernel.org/20260521202020.126500-2-maksym.shcherba@lnu.edu.ua Signed-off-by: Maksym Shcherba Reviewed-by: SeongJae Park Assisted-by: Antigravity:Gemini-3.1-Pro Signed-off-by: Andrew Morton

mm/damon/core: hide damon_destroy_region()

2026-06-04T21:45:01Z

damon_destroy_region() is being used by only DAMON core, but exposed to DAMON API callers. Exposing something that is not really being used by others will only increase the maintenance cost. Hide it. Link: https://lore.kernel.org/20260522154026.80546-8-sj@kernel.org Signed-off-by: SeongJae Park Cc: Brendan Higgins Cc: Shuah Khan Signed-off-by: Andrew Morton

mm/damon/core: hide damon_insert_region()

2026-06-04T21:45:01Z

damon_insert_region() is being used by only DAMON core, but exposed to DAMON API callers. Exposing something that is not really being used by others will only increase the maintenance cost. Hide it. Link: https://lore.kernel.org/20260522154026.80546-7-sj@kernel.org Signed-off-by: SeongJae Park Cc: Brendan Higgins Cc: Shuah Khan Signed-off-by: Andrew Morton

mm/damon/core: hide damon_add_region()

2026-06-04T21:45:00Z

damon_add_region() is being used by only DAMON core, but exposed to DAMON API callers. Exposing something that is not really being used by others will only increase the maintenance cost. Hide it. Link: https://lore.kernel.org/20260522154026.80546-6-sj@kernel.org Signed-off-by: SeongJae Park Cc: Brendan Higgins Cc: Shuah Khan Signed-off-by: Andrew Morton

mm/damon/sysfs: setup damon_filter->memcg_id from path

2026-06-02T22:22:31Z

Find and set the memcg_id for damon_filter from the user-passed memory cgroup path when updating the DAMON input parameters. Link: https://lore.kernel.org/20260518234119.97569-27-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Shuah Khan Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

mm/damon/core: introduce DAMON_FILTER_TYPE_MEMCG

2026-06-02T22:22:30Z

Belonging memory cgoup is another data attribute that can be useful to monitor. Introduce a new DAMON filter type, namely DAMON_FILTER_TYPE_MEMCG, for monitoring of this attribute. Link: https://lore.kernel.org/20260518234119.97569-23-sj@kernel.org Signed-off-by: SeongJae Park Cc: David Hildenbrand Cc: Jonathan Corbet Cc: Liam R. Howlett Cc: Lorenzo Stoakes Cc: "Masami Hiramatsu (Google)" Cc: Mathieu Desnoyers Cc: Michal Hocko Cc: Mike Rapoport Cc: Shuah Khan Cc: Steven Rostedt Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton