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Date:   Sun, 29 May 2022 15:04:26 +0800
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Subject: Re: [PATCH v2] erofs: leave compressed inodes unsupported in fscache
 mode for now
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To:     Jeffle Xu <jefflexu@linux.alibaba.com>, xiang@kernel.org,
        linux-erofs@lists.ozlabs.org
Cc:     linux-kernel@vger.kernel.org
References: <20220526010344.118493-1-jefflexu@linux.alibaba.com>
From:   Chao Yu <chao@kernel.org>
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On 2022/5/26 9:03, Jeffle Xu wrote:
> erofs over fscache doesn't support the compressed layout yet. It will
> cause NULL crash if there are compressed inodes contained when working
> in fscache mode.
> 
> So far in the erofs based container image distribution scenarios
> (RAFS v6), the compressed RAFS v6 images are downloaded and then
> decompressed on demand as an uncompressed erofs image. Then the erofs
> image is mounted in fscache mode for containers to use. IOWs, currently
> compressed data is decompressed on the userspace side instead and
> uncompressed erofs images will be finally cached.
> 
> The fscache support for the compressed layout is still under
> development and it will be used for runtime decompression feature.
> Anyway, to avoid the potential crash, let's leave the compressed inodes
> unsupported in fscache mode until we support it later.
> 
> Fixes: 1442b02b66ad ("erofs: implement fscache-based data read for non-inline layout")
> Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
> Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>

Reviewed-by: Chao Yu <chao@kernel.org>

Thanks,