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Subject: Re: [PATCH v2] erofs: fix bio->bi_max_vecs behavior change
To: Gao Xiang <hsiangkao@redhat.com>
References: <20210306033109.28466-1-hsiangkao@aol.com>
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From: Chao Yu <yuchao0@huawei.com>
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Date: Mon, 8 Mar 2021 10:52:19 +0800
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Cc: Martin DEVERA <devik@eaxlabs.cz>, linux-erofs@lists.ozlabs.org,
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On 2021/3/8 10:36, Gao Xiang wrote:
> Hi Chao,
> 
> On Mon, Mar 08, 2021 at 09:29:30AM +0800, Chao Yu wrote:
>> On 2021/3/6 12:04, Gao Xiang wrote:
>>> From: Gao Xiang <hsiangkao@redhat.com>
>>>
>>> Martin reported an issue that directory read could be hung on the
>>> latest -rc kernel with some certain image. The root cause is that
>>> commit baa2c7c97153 ("block: set .bi_max_vecs as actual allocated
>>> vector number") changes .bi_max_vecs behavior. bio->bi_max_vecs
>>> is set as actual allocated vector number rather than the requested
>>> number now.
>>>
>>> Let's avoid using .bi_max_vecs completely instead.
>>>
>>> Reported-by: Martin DEVERA <devik@eaxlabs.cz>
>>> Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
>>
>> Looks good to me, btw, it needs to Cc stable mailing list?
>>
>> Reviewed-by: Chao Yu <yuchao0@huawei.com>
>>
> 
> Thanks for your review. <= 5.11 kernels are not impacted.
> For now, this only impacts 5.12-rc due to a bio behavior
> change (see commit baa2c7c97153). So personally I think
> just leave as it is is fine.

Okay, so that's fine if you send pull request before 5.12 formal release. ;)

Thanks,

> 
> Thanks,
> Gao Xiang
> 
>> Thanks,
>>
> 
> .
>