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Date:   Thu, 19 Jan 2023 20:50:31 -0700
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Subject: Re: [PATCH-next v3] lib: parser: optimize match_NUMER apis to use
 local array
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To:     Tejun Heo <tj@kernel.org>, Li Lingfeng <lilingfeng3@huawei.com>
Cc:     linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        akpm@linux-foundation.org, jack@suse.cz, bingjingc@synology.com,
        ebiggers@google.com, james.smart@broadcom.com, houtao1@huawei.com,
        yi.zhang@huawei.com, yangerkun@huawei.com, yukuai3@huawei.com
References: <20230120021304.5773-1-lilingfeng3@huawei.com>
 <Y8n1rOLdMGDfOgpe@slm.duckdns.org>
From:   Jens Axboe <axboe@kernel.dk>
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On 1/19/23 7:00?PM, Tejun Heo wrote:
> On Fri, Jan 20, 2023 at 10:13:04AM +0800, Li Lingfeng wrote:
>> Memory will be allocated to store substring_t in match_strdup(), which means
>> the caller of match_strdup() may need to be scheduled out to wait for reclaiming
>> memory.
>>
>> Using local array to store substring_t to remove the restriction.
>>
>> Link: https://lore.kernel.org/all/20221104023938.2346986-5-yukuai1@huaweicloud.com/
>> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com>
> 
>  Acked-by: Tejun Heo <tj@kernel.org>
> 
> This fixes a sleep-while-atomic splat in blk-iocost, so it'd be a good idea to add:
> 
>  Fixes: 2c0647988433 ("blk-iocost: don't release 'ioc->lock' while updating params").
> 
> The mm tree likely is the best fit but given the splat the block tree can
> work too. Andrew, Jens, what do you think?

I can take it through the block tree once folks are happy with it, as
the buggy patch came through there. Doesn't really matter to me,
however.

Why is it marked for-next though, seems like this is a regression in
this series?

-- 
Jens Axboe