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Subject: Re: [PATCH bpf v2] xdp: fix race on generic receive path
To:     Ilya Maximets <i.maximets@samsung.com>, netdev@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
        xdp-newbies@vger.kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn.topel@intel.com>,
        Magnus Karlsson <magnus.karlsson@intel.com>,
        Jonathan Lemon <jonathan.lemon@gmail.com>,
        Jakub Kicinski <jakub.kicinski@netronome.com>,
        Alexei Starovoitov <ast@kernel.org>
References: <CGME20190703120922eucas1p2d97e3b994425ecdd2dadd13744ac2a77@eucas1p2.samsung.com>
 <20190703120916.19973-1-i.maximets@samsung.com>
From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <1ac9c018-09c0-1123-ed97-b230a2117533@iogearbox.net>
Date:   Tue, 9 Jul 2019 02:13:21 +0200
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On 07/03/2019 02:09 PM, Ilya Maximets wrote:
> Unlike driver mode, generic xdp receive could be triggered
> by different threads on different CPU cores at the same time
> leading to the fill and rx queue breakage. For example, this
> could happen while sending packets from two processes to the
> first interface of veth pair while the second part of it is
> open with AF_XDP socket.
> 
> Need to take a lock for each generic receive to avoid race.
> 
> Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support")
> Signed-off-by: Ilya Maximets <i.maximets@samsung.com>

Applied, thanks!