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Date:   Mon, 24 Oct 2022 10:35:23 -0700
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Subject: [PATCH v1 8/8] perf trace: Use sig_atomic_t to avoid UB
From:   Ian Rogers <irogers@google.com>
To:     Leo Yan <leo.yan@linaro.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>,
        German Gomez <german.gomez@arm.com>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Cc:     Stephane Eranian <eranian@google.com>,
        Ian Rogers <irogers@google.com>
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Precedence: bulk

Use sig_atomic_t for variables written/accessed in signal
handlers. This is undefined behavior as per:
https://wiki.sei.cmu.edu/confluence/display/c/SIG31-C.+Do+not+access+shared+objects+in+signal+handlers

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/builtin-trace.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index d3c757769b96..72991528687e 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1535,8 +1535,8 @@ static size_t trace__fprintf_tstamp(struct trace *trace, u64 tstamp, FILE *fp)
 }
 
 static pid_t workload_pid = -1;
-static bool done = false;
-static bool interrupted = false;
+static volatile sig_atomic_t done = false;
+static volatile sig_atomic_t interrupted = false;
 
 static void sighandler_interrupt(int sig __maybe_unused)
 {
-- 
2.38.0.135.g90850a2211-goog