Re: [PATCH] mm/damon: validate addr_unit to be power of 2

[SeongJae Park <sj@kernel.org>]

On Sat, 28 Mar 2026 10:26:51 +0800 Liew Rui Yan <aethernet65535@gmail.com> wrote:

[...]
> Just to make sure I captured the full context, in my earlier follow-ups
> [1][2] (in case they got folded in your email client):
> 
> - Does the current kdamond termination on invalid user input align with
>   your design goal mentioned in [3] (stopping only for "internal
>   errors")?

No.  I still think it would be better to avoid wrong input-caused termination.
But in a simple way.  Also, it would be better to be consistent.

> 
> - Would a lightweight fix be acceptable? For example, performing
>   validation at the very beginning of damon_commit_ctx(), and returning
>   -EINVAL before setting 'maybe_corrupted' to true. Since no
>   modifications to 'dst' would have occurred, kdamond could safely
>   continue with its old configuration.

I suggested you to try something similar to what DAMON_SYSFS is doing.  But I
didn't get your response to the idea yet.  Could you please let me know what do
you think about the approach?

> 
> Thank you again for your time, and guidance. :>

You're welcome.

> 
> [1] https://lore.kernel.org/20260327064517.68131-1-aethernet65535@gmail.com
> [2] https://lore.kernel.org/20260327121009.38374-1-aethernet65535@gmail.com
> [3] https://lore.kernel.org/20260319151528.86490-1-sj@kernel.org


Thanks,
SJ

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