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Date:   Wed, 25 Sep 2019 16:43:11 -0700
Message-Id: <20190925234312.94063-1-allanzhang@google.com>
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Subject: [PATCH 0/1] bpf: Fix bpf_event_output re-entry issue
From:   Allan Zhang <allanzhang@google.com>
To:     daniel@iogearbox.net, songliubraving@fb.com,
        netdev@vger.kernel.org, bpf@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, Allan Zhang <allanzhang@google.com>
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BPF_PROG_TYPE_SOCK_OPS program can reenter bpf_event_output because it can
be called from atomic and non-atomic contexts since we don't have
bpf_prog_active to prevent it happen.

This patch enables 3 level of nesting to support normal, irq and nmi
context.

We can easily reproduce the issue by running neper crr mode with 100 flows
and 10 threads from neper client side.

Allan Zhang (1):
  bpf: Fix bpf_event_output re-entry issue

 kernel/trace/bpf_trace.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

-- 
2.23.0.351.gc4317032e6-goog