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From:   Amir Goldstein <amir73il@gmail.com>
Date:   Thu, 18 Feb 2021 11:10:00 +0200
Message-ID: <CAOQ4uxgreB=TywvWQXfcHYMBcFm5OKSdwUC8YJY1WuVja6PccQ@mail.gmail.com>
Subject: Re: [PATCH v2] vfs: prevent copy_file_range to copy across devices
To:     Christoph Hellwig <hch@infradead.org>
Cc:     Luis Henriques <lhenriques@suse.de>,
        Jeff Layton <jlayton@kernel.org>,
        Steve French <sfrench@samba.org>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna.schumaker@netapp.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Dave Chinner <dchinner@redhat.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        Nicolas Boichat <drinkcat@chromium.org>,
        Ian Lance Taylor <iant@google.com>,
        Luis Lozano <llozano@chromium.org>,
        ceph-devel <ceph-devel@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        CIFS <linux-cifs@vger.kernel.org>,
        samba-technical <samba-technical@lists.samba.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
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On Thu, Feb 18, 2021 at 9:42 AM Christoph Hellwig <hch@infradead.org> wrote:
>
> Looks good:
>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
>
> This whole idea of cross-device copie has always been a horrible idea,
> and I've been arguing against it since the patches were posted.

Ok. I'm good with this v2 as well, but need to add the fallback to
do_splice_direct()
in nfsd_copy_file_range(), because this patch breaks it.

And the commit message of v3 is better in describing the reported issue.

Thanks,
Amir.