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From:   Daeho Jeong <daeho43@gmail.com>
Date:   Fri, 4 Dec 2020 13:31:02 +0900
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Subject: Re: [f2fs-dev] [PATCH] f2fs: fix race of pending_pages in decompression
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
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> Are you sure?  I thought that compression (and encryption) apply to the whole
> file, including any Merkle tree blocks past i_size.

This "dic" structure is only for "de"compression, so we don't need to
worry about going beyond i_size case.

> Also, even if you include the i_size check, it's still wrong to check
> fsverity_active() in the middle of the I/O because FS_IOC_ENABLE_VERITY can
> execute concurrently, causing fsverity_active() to return false at the beginning
> of the I/O and true later in the I/O.  It needs to be checked only once, at the
> beginning...

Got it. Our previous implementation didn't consider this case. Need to fix this.

Thanks,