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        Fri, 10 Aug 2018 07:09:53 -0400
Subject: Re: [PATCH v3] f2fs: checkpoint disabling
To: Daniel Rosenberg <drosen@google.com>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        Jonathan Corbet <corbet@lwn.net>,
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From: Chao Yu <yuchao0@huawei.com>
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Date: Fri, 10 Aug 2018 16:40:53 +0800
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Hi Daniel,

On 2018/8/8 7:48, Daniel Rosenberg wrote:
> This adds a lightweight non-persistent snapshotting scheme to f2fs.
> 
> To use, mount with the option checkpoint=disable, and to return to
> normal operation, remount with checkpoint=enable. If the filesystem
> is shut down before remounting with checkpoint=enable, it will revert
> back to its apparent state when it was first mounted with
> checkpoint=disable. This is useful for situations where you wish to be
> able to roll back the state of the disk in case of some critical
> failure.

When filesystem is full, statfs shown abnormally as below:

/dev/zram0       2095104 -17177769548 17179864652    - /mnt/f2fs

I guess it's related to this patch, could you have a look at this?

Thanks,