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Date:   Mon, 18 Mar 2019 16:15:29 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Prateek Sood <prsood@codeaurora.org>, mingo@redhat.com,
        linux-kernel@vger.kernel.org, sramana@codeaurora.org,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Jiri Olsa <jolsa@redhat.com>
Subject: Re: [PATCH] perf: extend total_ref_count usage to protect
 perf_trace_buf access
Message-ID: <20190318151529.GT6058@hirez.programming.kicks-ass.net>
References: <1552906065-24137-1-git-send-email-prsood@codeaurora.org>
 <20190318110250.7214cfa7@gandalf.local.home>
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On Mon, Mar 18, 2019 at 11:02:50AM -0400, Steven Rostedt wrote:
> On Mon, 18 Mar 2019 16:17:45 +0530
> Prateek Sood <prsood@codeaurora.org> wrote:
> 
> > A potential race exists between access of perf_trace_buf[i] from
> > perf_trace_buf_alloc() and perf_trace_event_unreg(). This can
> > result in perf_trace_buf[i] being NULL during access from memset()
> > in perf_trace_buf_alloc().

Can you expound?