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Subject: Re: [PATCH bpf-next v3 2/4] libfs: support RENAME_EXCHANGE in
 simple_rename()
To:     Miklos Szeredi <miklos@szeredi.hu>,
        Lorenz Bauer <lmb@cloudflare.com>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Miklos Szeredi <mszeredi@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        network dev <netdev@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>,
        Christian Brauner <christian@brauner.io>
References: <20211028094724.59043-1-lmb@cloudflare.com>
 <20211028094724.59043-3-lmb@cloudflare.com>
 <CAJfpegvPrQBnYO3XNcCHODBBCXm6uH73zOWXs+sfn=3LQmMyww@mail.gmail.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <7988de27-1718-60c1-ec03-9343d2cc460f@iogearbox.net>
Date:   Tue, 2 Nov 2021 11:11:02 +0100
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On 11/2/21 10:25 AM, Miklos Szeredi wrote:
> On Thu, 28 Oct 2021 at 11:48, Lorenz Bauer <lmb@cloudflare.com> wrote:
>>
>> Allow atomic exchange via RENAME_EXCHANGE when using simple_rename.
>> This affects binderfs, ramfs, hubetlbfs and bpffs.
> 
> Ramfs and hugetlbfs are generic enough; those seem safe.
> 
> Binderfs: I have no idea what this does; binderfs_rename() should
> probably error out on RENAME_EXCHANGE for now, or an explicit ack from
> the maintainers.

Thanks for the review, Miklos! Adding Christian to Cc wrt binderfs ... full context
for all patches: https://lore.kernel.org/bpf/20211028094724.59043-1-lmb@cloudflare.com/

> Bpffs is your baby...
> 
> Thanks,
> Miklos
>