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From: Ian Rogers <irogers@google.com> stable inclusion from stable-v6.6.2 commit c139d4d928f452415636aa456a91be852c29de67 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I8IW7G Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit ab8ce150781d326c6bfbe1e09f175ffde1186f80 ] Running perf top with address sanitizer and "--call-graph=lbr" fails due to reading sample 0 when no samples exist. Add a guard to prevent this. Fixes: e2b23483eb1d ("perf machine: Factor out lbr_callchain_add_lbr_ip()") Signed-off-by: Ian Rogers <irogers@google.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: German Gomez <german.gomez@arm.com> Cc: James Clark <james.clark@arm.com> Cc: Nick Terrell <terrelln@fb.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: liuwenyu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Song Liu <song@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20231024222353.3024098-3-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> --- tools/perf/util/machine.c | 22 ++++++++++++---------- 1 file changed, 12 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index 88f31b3a63ac..e6a8d758f6fe 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2624,16 +2624,18 @@ static int lbr_callchain_add_lbr_ip(struct thread *thread, save_lbr_cursor_node(thread, cursor, i); } - /* Add LBR ip from first entries.to */ - ip = entries[0].to; - flags = &entries[0].flags; - *branch_from = entries[0].from; - err = add_callchain_ip(thread, cursor, parent, - root_al, &cpumode, ip, - true, flags, NULL, - *branch_from); - if (err) - return err; + if (lbr_nr > 0) { + /* Add LBR ip from first entries.to */ + ip = entries[0].to; + flags = &entries[0].flags; + *branch_from = entries[0].from; + err = add_callchain_ip(thread, cursor, parent, + root_al, &cpumode, ip, + true, flags, NULL, + *branch_from); + if (err) + return err; + } return 0; } -- 2.25.1