Re: [PATCH] blk-throttle: Calculate allowed value only when the throttle is enabled

[Tejun Heo]

Hello,

On Thu, Sep 28, 2023 at 09:58:58AM +0800, linan666@xxxxxxxxxxxxxxx wrote:
> From: Li Nan <linan122@xxxxxxxxxx>
> 
> When the throttle of bps is not enabled, tg_bps_limit() returns U64_MAX,
> which is be used in calculate_bytes_allowed(), and divide 0 error will
> happen.

calculate_bytes_allowed() is just

  return mul_u64_u64_div_u64(bps_limit, (u64)jiffy_elapsed, (u64)HZ); 

The only division is by HZ. How does divide by 0 happen?

Thanks.

-- 
tejun