Subject: Re: [PATCH -next v3 0/3] blk-cgroup: make sure pd_free_fn() is called
 in order
To:     Jens Axboe <axboe@kernel.dk>, Yu Kuai <yukuai1@huaweicloud.com>,
        tj@kernel.org, hch@lst.de, josef@toxicpanda.com
Cc:     cgroups@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, yi.zhang@huawei.com,
        yangerkun@huawei.com, "yukuai (C)" <yukuai3@huawei.com>
References: <20230119110350.2287325-1-yukuai1@huaweicloud.com>
 <bd1c347b-cbf8-3917-401a-ed85c6ccb956@kernel.dk>
From:   Yu Kuai <yukuai1@huaweicloud.com>
Message-ID: <0ddce9e4-d027-0bb0-d260-093ccc4c2d4d@huaweicloud.com>
Date:   Sun, 29 Jan 2023 14:06:11 +0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <bd1c347b-cbf8-3917-401a-ed85c6ccb956@kernel.dk>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 8bit
Precedence: bulk

Hi, Jens

在 2023/01/20 2:54, Jens Axboe 写道:
> On 1/19/23 4:03 AM, Yu Kuai wrote:
>> From: Yu Kuai <yukuai3@huawei.com>
>>
>> Changes in v3:
>>   - add ack tag from Tejun for patch 1,2
>>   - as suggested by Tejun, update commit message and comments in patch 3
>>
>> The problem was found in iocost orignally([1]) that ioc can be freed in
>> ioc_pd_free(). And later we found that there are more problem in
>> iocost([2]).
>>
>> After some discussion, as suggested by Tejun([3]), we decide to fix the
>> problem that parent pd can be freed before child pd in cgroup layer
>> first. And the problem in [1] will be fixed later if this patchset is
>> applied.
> 
> Doesn't apply against for-6.3/block (or linux-next or my for-next, for
> that matter). Can you resend a tested one against for-6.3/block?
> 

This is weird, I just test latest linux-next, and I can apply this
patchset on the top of following commit:

For latest for-6.3/block, this patch 2 can't be applied because
following commit is not here:

e3ff8887e7db blk-cgroup: fix missing pd_online_fn() while activating policy

But this patch is already merged into 6.2-rc5.

Thanks,
Kuai