5.15-stable review patch. If anyone has any objections, please let me know.
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From: Adrian Hunter adrian.hunter@intel.com
[ Upstream commit e101a05f79fd4ee3e89d2f3fb716493c33a33708 ]
MemorySanitizer discovered instances where the instruction op value was not assigned.:
WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x5581c00a76b3 in intel_pt_sample_flags tools/perf/util/intel-pt.c:1527:17 Uninitialized value was stored to memory at #0 0x5581c005ddf8 in intel_pt_walk_insn tools/perf/util/intel-pt-decoder/intel-pt-decoder.c:1256:25
The op value is used to set branch flags for branch instructions encountered when walking the code, so fix by setting op to INTEL_PT_OP_OTHER in other cases.
Fixes: 4c761d805bb2d2ea ("perf intel-pt: Fix intel_pt_fup_event() assumptions about setting state type") Reported-by: Ian Rogers irogers@google.com Signed-off-by: Adrian Hunter adrian.hunter@intel.com Tested-by: Ian Rogers irogers@google.com Cc: Jiri Olsa jolsa@kernel.org Cc: Namhyung Kim namhyung@kernel.org Closes: https://lore.kernel.org/linux-perf-users/20240320162619.1272015-1-irogers@go... Link: https://lore.kernel.org/r/20240326083223.10883-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++ tools/perf/util/intel-pt.c | 2 ++ 2 files changed, 4 insertions(+)
diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c index b9f94f198a3eb..3530551b82819 100644 --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1215,6 +1215,8 @@ static bool intel_pt_fup_event(struct intel_pt_decoder *decoder) bool ret = false;
decoder->state.type &= ~INTEL_PT_BRANCH; + decoder->state.insn_op = INTEL_PT_OP_OTHER; + decoder->state.insn_len = 0;
if (decoder->set_fup_tx_flags) { decoder->set_fup_tx_flags = false; diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c index 805bad9364e94..b00776c65c186 100644 --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -721,6 +721,7 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn, bool nr;
intel_pt_insn->length = 0; + intel_pt_insn->op = INTEL_PT_OP_OTHER;
if (to_ip && *ip == to_ip) goto out_no_cache; @@ -816,6 +817,7 @@ static int intel_pt_walk_next_insn(struct intel_pt_insn *intel_pt_insn,
if (to_ip && *ip == to_ip) { intel_pt_insn->length = 0; + intel_pt_insn->op = INTEL_PT_OP_OTHER; goto out_no_cache; }