From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jens Axboe <axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org>
Subject: Re: [PATCH block/for-next] blk-iocost: fix divide-by-zero in
 transfer_surpluses()
Date: Fri, 11 Sep 2020 11:10:58 -0600
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References: <20200911170746.GG4295@mtj.thefacebook.com>
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To: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

On 9/11/20 11:07 AM, Tejun Heo wrote:
> Conceptually, root_iocg->hweight_donating must be less than WEIGHT_ONE but
> all hweight calculations round up and thus it may end up >= WEIGHT_ONE
> triggering divide-by-zero and other issues. Bound the value to avoid
> surprises.

Applied, thanks.

-- 
Jens Axboe