[PATCH 0/2] mm/damon/sysfs: fix refresh_ms control overwriting on multi-kdamonds usages

[SeongJae Park <sj@kernel.org>]

Automatic esssential DAMON/DAMOS status update feature of DAMON sysfs
interface (refresh_ms) is broken [1] for multiple DAMON contexts
(kdamonds) use case, since it uses a global single damon_call_control
object for all created DAMON contexts.  The fields of the object,
particularly the list field is over-written for the contexts and it
makes unexpected results including user-space hangup and kernel crashes
[2].  Fix it by extending damon_call_control for the use case and
updating the usage on DAMON sysfs interface to use per-context
dynamically allocated damon_call_control object.

[1] https://lore.kernel.org/20250904011738.930-1-yunjeong.mun@sk.com
[2] https://lore.kernel.org/20250905035411.39501-1-sj@kernel.org

SeongJae Park (2):
  mm/damon/core: introduce damon_call_control->dealloc_on_cancel
  mm/damon/sysfs: use dynamically allocated repeat mode
    damon_call_control

 include/linux/damon.h |  2 ++
 mm/damon/core.c       |  8 ++++++--
 mm/damon/sysfs.c      | 23 +++++++++++++++--------
 3 files changed, 23 insertions(+), 10 deletions(-)


base-commit: c6680f5947fa5ff95bc881f2c4e36443478c8829
-- 
2.39.5