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Subject: Re: [PATCH -next v2 2/9] blk-iocost: improve hanlder of match_u64()
To:     Tejun Heo <tj@kernel.org>, Li Nan <linan122@huawei.com>
Cc:     josef@toxicpanda.com, axboe@kernel.dk, cgroups@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com, "yukuai (C)" <yukuai3@huawei.com>
References: <20221130132156.2836184-1-linan122@huawei.com>
 <20221130132156.2836184-3-linan122@huawei.com>
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From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <7e4f1cea-2691-9b81-35f6-0dd236149f56@huaweicloud.com>
Date:   Thu, 1 Dec 2022 10:15:53 +0800
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Hi,

?? 2022/12/01 4:32, Tejun Heo д??:
> On Wed, Nov 30, 2022 at 09:21:49PM +0800, Li Nan wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> 1) There are one place that return value of match_u64() is not checked.
>> 2) If match_u64() failed, return value is set to -EINVAL despite that
>>     there are other possible errnos.
> 
> Ditto. Does this matter?
> 

It's not a big deal, but I think at least return value of match_u64()
should be checked, we don't want to continue with invalid input, right?

By the way, match_u64() can return -ERANGE, which can provide more
specific error messge to user.

Thanks,
Kuai