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While damon_commit_ctx() correctly detects this and returns -EINVAL, it sets the 'maybe_corrupted' flag during this process. This flag causes the running kdamond to terminate. While the termination is a safety measure, it is suboptimal in this case because the error is just a simple invalid input from the user, which shouldn't neccessitate stopping the kdamond. Solution ======== Add an early validation in damon_lru_sort_apply_parameters() and damon_reclaim_apply_parameters() to check 'min_region_sz' before any state change occurs. If it is non-power-of-2, return -EINVAL immediately, preventing 'maybe_corrupted' from being set. Patch 1 fixes the issue for DAMON_LRU_SORT. Patch 2 fixes the issue for DAMON_RECLAIM. Changes from v4 (https://lore.kernel.org/20260410044259.95877-1-aethernet65535@gmail.com) - Clarify this is only a minor user experience improvement. - Remove Fixes: and Cc: stable tags. Changes from v3 (https://lore.kernel.org/20260403052837.58063-1-aethernet65535@gmail.com) - Improve commit message: clarify "unexpected termination". - Add detailed User Impact with reason why kdamond cannot be restarted. Changes from v2 (https://lore.kernel.org/20260402053756.26606-1-aethernet65535@gmail.com) - Split the patch into two per-module patches. - Add Fixes: and Cc: stable tags. - Elaborate user impact and reproduction steps. Changes from v1 (https://lore.kernel.org/20260331073231.30060-1-aethernet65535@gmail.com) - Fix memory leak issue. Changes from first attempt (https://lore.kernel.org/20260327062627.66426-1-aethernet65535@gmail.com) - Renamed the subject. - Validate min_region_sz rather than addr_unit. Liew Rui Yan (2): mm/damon/lru_sort: validate min_region_size to be power of 2 mm/damon/reclaim: validate min_region_size to be power of 2 mm/damon/lru_sort.c | 5 +++++ mm/damon/reclaim.c | 5 +++++ 2 files changed, 10 insertions(+) -- 2.53.0