Re: [RFC PATCH v1.3 3/4] mm/damon/core: copy nid for eligible_mem_bp damos quota goal commit

[sashiko-bot@kernel.org]

> damos_commit_quota_goal_union() is not updating the ->nid union field
> when the goal metric is DAMOS_QUITA_NODE_ELIGIBLE_MEM_BP.  Hence, if a
> DAMOS quota goal of the type is online committed in a way that it will
> reuse other quota goal's memory space, the new goal will work with a
> garbage nid value.  As a result, the DAMOS scheme can show unexpected
> aggressiveness.  Do the update.
> 
> The user impact is not catastrophic.  No leak or crash happens.  Doing
> the quota goal online commit that can reproduce the issue is expected to
> be not common.  This issue was not found by real users but the AI
> review.  That said, the issue can reliably be reproduced.
> 
> This issue was discovered [1] by Sashiko.
> 
> [1] https://lore.kkernel.org/20260827045035.94611-1-sj@kernel.org
> 
> Fixes: 9138e27a3bc3 ("mm/damon: add node_eligible_mem_bp goal metric")
> Cc: <stable@vger.kernel.org> # 7.2.x
> Signed-off-by: SJ Park <sj@kernel.org>

Sashiko has reviewed this patch and found no issues. It looks great!

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Sashiko AI review · https://sashiko.dev/#/patchset/20260828183649.71192-1-sj@kernel.org?part=3