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        Nicholas Piggin <npiggin@gmail.com>,
        Jisheng Zhang <jszhang@kernel.org>, linux-csky@vger.kernel.org,
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Subject: [PATCH 0/2] ftrace: make sure preemption disabled on recursion
 testing
Message-ID: <8c7de46d-9869-aa5e-2bb9-5dbc2eda395e@linux.alibaba.com>
Date:   Tue, 12 Oct 2021 13:39:16 +0800
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The testing show that perf_ftrace_function_call() are using
smp_processor_id() with preemption enabled, all the checking
on CPU could be wrong after preemption, PATCH 1/2 will fix
that.

Besides, as Peter point out, the testing of recursion within
the section between ftrace_test_recursion_trylock()/_unlock()
pair also need the preemption disabled as the documentation
explained, PATCH 2/2 will make sure on that.

Michael Wang (2):
  ftrace: disable preemption on the testing of recursion
  ftrace: prevent preemption in perf_ftrace_function_call()

 arch/csky/kernel/probes/ftrace.c     |  2 --
 arch/parisc/kernel/ftrace.c          |  2 --
 arch/powerpc/kernel/kprobes-ftrace.c |  2 --
 arch/riscv/kernel/probes/ftrace.c    |  2 --
 arch/x86/kernel/kprobes/ftrace.c     |  2 --
 include/linux/trace_recursion.h      | 10 +++++++++-
 kernel/livepatch/patch.c             |  6 ------
 kernel/trace/trace_event_perf.c      | 17 +++++++++++++----
 kernel/trace/trace_functions.c       |  5 -----
 9 files changed, 22 insertions(+), 26 deletions(-)

-- 
1.8.3.1