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Date:   Fri, 11 Aug 2023 15:25:25 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Zheng Yejian <zhengyejian1@huawei.com>
Cc:     <mhiramat@kernel.org>, <laijs@cn.fujitsu.com>,
        <linux-kernel@vger.kernel.org>,
        <linux-trace-kernel@vger.kernel.org>
Subject: Re: [PATCH] tracing: Fix race when concurrently splice_read
 trace_pipe
Message-ID: <20230811152525.2511f8f0@gandalf.local.home>
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On Thu, 10 Aug 2023 20:39:05 +0800
Zheng Yejian <zhengyejian1@huawei.com> wrote:

> When concurrently splice_read file trace_pipe and per_cpu/cpu*/trace_pipe,
> there are more data being read out than expected.

Honestly the real fix is to prevent that use case. We should probably have
access to trace_pipe lock all the per_cpu trace_pipes too.

-- Steve