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From:   Chao Yu <yuchao0@huawei.com>
Subject: [PATCH] f2fs: avoid GC causing encrypted file corrupted
To:     Chao Yu <chao@kernel.org>, Yunlong Song <yunlong.song@huawei.com>,
        <jaegeuk@kernel.org>, <yunlong.song@icloud.com>
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        <shengyong1@huawei.com>, <heyunlei@huawei.com>,
        <linux-f2fs-devel@lists.sourceforge.net>,
        <linux-kernel@vger.kernel.org>
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Message-ID: <5c3d6053-e03a-8c61-0a07-07d0090ba349@huawei.com>
Date:   Tue, 13 Nov 2018 11:16:24 +0800
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Jaegeuk,

On 2018/9/18 21:21, Chao Yu wrote:
> On 2018/9/18 20:39, Yunlong Song wrote:
>> The encrypted file may be corrupted by GC in following case:
>>
>> Time 1: | segment 1 blkaddr = A |  GC -> | segment 2 blkaddr = B |
>> Encrypted block 1 is moved from blkaddr A of segment 1 to blkaddr B of
>> segment 2,
>>
>> Time 2: | segment 1 blkaddr = B |  GC -> | segment 3 blkaddr = C |
>>
>> Before page 1 is written back and if segment 2 become a victim, then
>> page 1 is moved from blkaddr B of segment 2 to blkaddr Cof segment 3,
>> during the GC process of Time 2, f2fs should wait for page 1 written back
>> before reading it, or move_data_block will read a garbage block from
>> blkaddr B since page is not written back to blkaddr B yet.
>>
>> Commit 6aa58d8a ("f2fs: readahead encrypted block during GC") introduce
>> ra_data_block to read encrypted block, but it forgets to add
>> f2fs_wait_on_page_writeback to avoid racing between GC and flush.
>>
>> Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
> 
> Reviewed-by: Chao Yu <yuchao0@huawei.com>

I've reviewed this patch, could you add missing tag in the patch located in
dev-test branch?

Thanks,

> 
> Thanks,
> 
> .
>