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Sender: Tejun Heo <htejun@gmail.com>
Date:   Fri, 20 Oct 2023 14:22:54 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Khazhismel Kumykov <khazhy@chromium.org>
Cc:     Josef Bacik <josef@toxicpanda.com>, Jens Axboe <axboe@kernel.dk>,
        Yu Kuai <yukuai3@huawei.com>, cgroups@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        oleg@redhat.com, linan122@huawei.com,
        Khazhismel Kumykov <khazhy@google.com>
Subject: Re: [PATCH] blk-throttle: check for overflow in
 calculate_bytes_allowed
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References: <20231020223617.2739774-1-khazhy@google.com>
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On Fri, Oct 20, 2023 at 03:36:17PM -0700, Khazhismel Kumykov wrote:
> Inexact, we may reject some not-overflowing values incorrectly, but
> they'll be on the order of exabytes allowed anyways.
> 
> This fixes divide error crash on x86 if bps_limit is not configured or
> is set too high in the rare case that jiffy_elapsed is greater than HZ.
> 
> Fixes: e8368b57c006 ("blk-throttle: use calculate_io/bytes_allowed() for throtl_trim_slice()")
> Fixes: 8d6bbaada2e0 ("blk-throttle: prevent overflow while calculating wait time")
> Signed-off-by: Khazhismel Kumykov <khazhy@google.com>

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun