Messages in this thread | | | Subject | Re: [PATCH v2 block/for-next] blk-iocost: fix divide-by-zero in transfer_surpluses() | From | Jens Axboe <> | Date | Fri, 11 Sep 2020 16:43:18 -0600 |
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On 9/11/20 4:40 PM, 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. > > Signed-off-by: Tejun Heo <tj@kernel.org> > Fixes: e08d02aa5fc9 ("blk-iocost: implement Andy's method for donation weight updates") > > Signed-off-by: Tejun Heo <tj@kernel.org> > --- > Jens, I was flipping between doing max_t(, 1) over the whole divider and > doing min_t(, WEIGHT_ONE - 1) for hweight_donating. I thought that I as > testing after the last change but it obviously wasn't and the previous patch > doesn't compile due to missing type argument. Can you please apply this > patch instead? I can send an incremental patch if that'd be better. My > apologies.
Sure, I replaced it. BTW, you had two signed-off-by's in there.
-- Jens Axboe
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