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Date:   Sun, 25 Sep 2022 09:08:39 +0800
From:   Leo Yan <leo.yan@linaro.org>
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>, Ingo Molnar <mingo@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        linux-perf-users@vger.kernel.org,
        Stephane Eranian <eranian@google.com>
Subject: Re: [PATCH 1/4] perf record: Fix a segfault in
 record__read_lost_samples()
Message-ID: <Yy+p41f19aiwi/cd@leoy-huanghe>
References: <20220923173142.805896-1-namhyung@kernel.org>
 <20220923173142.805896-2-namhyung@kernel.org>
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On Fri, Sep 23, 2022 at 10:31:39AM -0700, Namhyung Kim wrote:
> When it fails to open events record__open() returns without setting the
> session->evlist.  Then it gets a segfault in the function trying to read
> lost sample counts.  You can easily reproduce it as a normal user like:
> 
>   $ perf record -p 1 true
>   ...
>   perf: Segmentation fault
>   ...
> 
> Skip the function if it has no evlist.  And add more protection for evsels
> which are not properly initialized.
> 
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Tested-by: Leo Yan <leo.yan@linaro.org>