Re: [PATCH RFC v2 0/7] blk-iocost: support to build iocost as kernel module
From: Christoph Hellwig
Date: Tue Jun 18 2024 - 04:02:00 EST
On Tue, Jun 18, 2024 at 11:17:44AM +0800, Yu Kuai wrote:
> The motivation is that iocost is not used widely in our production, and
> some customers don't want to increase kernel size to enable iocost that
> they will never use, and it'll be painful to maintain a new downstream
> kernel. Hence it'll be beneficially to build iocost as kernel module:
>
> - Kernel Size and Resource Usage, modules are loaded only when their
> specific functionality is required.
>
> - Flexibility and Maintainability, allows for dynamic loading and unloading
> of modules at runtime without the need to recompile and restart the kernel,
> for example we can just replace blk-iocost.ko to fix iocost CVE in our
> production environment.
Given the amount of new exports and infrastructure it adds this still
feels like a bad tradeoff.