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Subject: Re: [PATCH] ubifs: Don't discard nodes in recovery when ecc err
 detected
To:     Richard Weinberger <richard.weinberger@gmail.com>
CC:     Richard Weinberger <richard@nod.at>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        "zhangyi (F)" <yi.zhang@huawei.com>,
        <linux-mtd@lists.infradead.org>,
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From:   Zhihao Cheng <chengzhihao1@huawei.com>
Message-ID: <ee6578cf-a4be-a4eb-30d9-379926e3ed1e@huawei.com>
Date:   Tue, 3 Mar 2020 14:13:00 +0800
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在 2020/3/3 5:14, Richard Weinberger 写道:
> On Mon, Mar 2, 2020 at 4:58 AM Zhihao Cheng <chengzhihao1@huawei.com> wrote:
>> I mean, the uncorrectable ECC error is caused by hardware which may lead
>> to corrupted nodes detected in UBIFS. I found uncorretable ECC errors on
>> my NAND, in the environment of high temperature and humidity.
>>
>> At present, UBIFS ignores all EBADMSG errors, so the corrupted node is
>> only considered in being caused by unfinished writing. I think UBIFS
>> should consider the corrupted area caused by ECC errors in process
>> ubifs_recover_leb(). no_more_nodes() will skip a read-write unit. Maybe
>> the corrupted area is skipped.
> Well, if your NAND data is corrupted by your environment UBIFS cannot
> do much. Sure, we can paper over some places but at the end of the day
> you will always lose.
>
> What if the UBI VID header becomes unreadable or the root node of the
> index tree?
>
Agree, thanks for reminding.