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Subject: Re: [PATCH v2] staging: erofs: add SPDX identifer
From:   Gao Xiang <gaoxiang25@huawei.com>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC:     <devel@driverdev.osuosl.org>, <linux-erofs@lists.ozlabs.org>,
        "Loic Tourlonias" <loic.tourlonias.lkml@gmail.com>,
        <linux-kernel@vger.kernel.org>
References: <20181008141409.2624-1-loic.tourlonias.lkml@gmail.com>
 <20181008142228.GB13359@kroah.com>
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Message-ID: <3dedd0e3-f5eb-8131-a1e9-f04624381cd8@huawei.com>
Date:   Mon, 8 Oct 2018 22:41:53 +0800
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On 2018/10/8 22:36, Gao Xiang wrote:
> Hi Greg,
> 
> On 2018/10/8 22:22, Greg Kroah-Hartman wrote:
>> Why delete that line?
>>
>> But wait, why do we even have this file at all?  What's wrong with the
>> lib/lz4/ code that we have in the kernel today?  Shouldn't the code
>> using these files be moved over to use the lib/ code instead and this
>> file be deleted?
> 
> EROFS uses customized LZ4 decompression code for now (which has been offically
> supported in lz4 1.8.3, I have updated it in
> https://ozlabs.org/~akpm/mmots/broken-out/lib-lz4-update-lz4-decompressor-module.patch
> if it is shown up in Linux 4.20, I will remove all the customized LZ4 decompression code),
> but lib/ code lz4def.h isn't export to include/.

Please refer to https://github.com/lz4/lz4/issues/566 for more details the reason why
EROFS uses the different implementation rather than the current lib/lz4/ code in the kernel today
(it will be changed in the next Linux version if the updated code works fine.)

Thanks,
Gao Xiang

> 
> Thanks,
> Gao Xiang
> 
>>
>> thanks,
>>
>> greg k-h