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Date:   Tue, 18 Dec 2018 23:19:14 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        "Darrick J. Wong" <darrick.wong@oracle.com>, ebiggers@kernel.org,
        linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        "Theodore Y . Ts'o" <tytso@mit.edu>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        Victor Hsieh <victorhsieh@google.com>,
        Chandan Rajendra <chandan@linux.vnet.ibm.com>
Subject: Re: [PATCH v2 01/12] fs-verity: add a documentation file
Message-ID: <20181219071914.GA18852@infradead.org>
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On Tue, Dec 18, 2018 at 11:16:08PM -0800, Linus Torvalds wrote:
> On Tue, Dec 18, 2018, 23:11 Christoph Hellwig <hch@infradead.org wrote:
> 
> >
> > I think the fd would have to be on the same fs for this interface to
> > make sense. But it could be an O_TMPFILE one.  And given that ext4
> > already supports a variant of swapext this interface should also work
> > with the existing ext4 on disk format.
> >
> 
> Why is the merkle tree not just an xattr of the file?

Because it is too large for our awkward xattrs interface..