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Date:   Thu,  5 Oct 2023 16:08:42 -0700
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Subject: [PATCH v2 09/18] perf mem-events: Avoid uninitialized read
From:   Ian Rogers <irogers@google.com>
To:     Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>,
        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>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Yicong Yang <yangyicong@hisilicon.com>,
        Jonathan Cameron <jonathan.cameron@huawei.com>,
        Yang Jihong <yangjihong1@huawei.com>,
        Kan Liang <kan.liang@linux.intel.com>,
        Ming Wang <wangming01@loongson.cn>,
        Huacai Chen <chenhuacai@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        K Prateek Nayak <kprateek.nayak@amd.com>,
        Yanteng Si <siyanteng@loongson.cn>,
        Yuan Can <yuancan@huawei.com>,
        Ravi Bangoria <ravi.bangoria@amd.com>,
        James Clark <james.clark@arm.com>, llvm@lists.linux.dev,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        bpf@vger.kernel.org
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Precedence: bulk

pmu should be initialized to NULL before perf_pmus__scan loop. Fix and
shrink the scope of pmu at the same time. Issue detected by clang-tidy.

Fixes: 5752c20f3787 ("perf mem: Scan all PMUs instead of just core ones")
Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/util/mem-events.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c
index 39ffe8ceb380..954b235e12e5 100644
--- a/tools/perf/util/mem-events.c
+++ b/tools/perf/util/mem-events.c
@@ -185,7 +185,6 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
 {
 	int i = *argv_nr, k = 0;
 	struct perf_mem_event *e;
-	struct perf_pmu *pmu;
 
 	for (int j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
 		e = perf_mem_events__ptr(j);
@@ -202,6 +201,8 @@ int perf_mem_events__record_args(const char **rec_argv, int *argv_nr,
 			rec_argv[i++] = "-e";
 			rec_argv[i++] = perf_mem_events__name(j, NULL);
 		} else {
+			struct perf_pmu *pmu = NULL;
+
 			if (!e->supported) {
 				perf_mem_events__print_unsupport_hybrid(e, j);
 				return -1;
-- 
2.42.0.609.gbb76f46606-goog