The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 4624f199327a704dd1069aca1c3cadb8f2a28c6f Mon Sep 17 00:00:00 2001 From: Zechuan Chen chenzechuan1@huawei.com Date: Tue, 28 Dec 2021 19:13:38 +0800 Subject: [PATCH] perf probe: Fix ppc64 'perf probe add events failed' case
Because of commit bf794bf52a80c627 ("powerpc/kprobes: Fix kallsyms lookup across powerpc ABIv1 and ABIv2"), in ppc64 ABIv1, our perf command eliminates the need to use the prefix "." at the symbol name.
But when the command "perf probe -a schedule" is executed on ppc64 ABIv1, it obtains two symbol address information through /proc/kallsyms, for example:
cat /proc/kallsyms | grep -w schedule c000000000657020 T .schedule c000000000d4fdb8 D schedule
The symbol "D schedule" is not a function symbol, and perf will print: "p:probe/schedule _text+13958584"Failed to write event: Invalid argument
Therefore, when searching symbols from map and adding probe point for them, a symbol type check is added. If the type of symbol is not a function, skip it.
Fixes: bf794bf52a80c627 ("powerpc/kprobes: Fix kallsyms lookup across powerpc ABIv1 and ABIv2") Signed-off-by: Zechuan Chen chenzechuan1@huawei.com Acked-by: Masami Hiramatsu mhiramat@kernel.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Ingo Molnar mingo@redhat.com Cc: Jianlin Lv Jianlin.Lv@arm.com Cc: Jin Yao yao.jin@linux.intel.com Cc: Jiri Olsa jolsa@redhat.com Cc: Mark Rutland mark.rutland@arm.com Cc: Michael Ellerman mpe@ellerman.id.au Cc: Namhyung Kim namhyung@kernel.org Cc: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com Cc: Peter Zijlstra peterz@infradead.org Cc: Ravi Bangoria ravi.bangoria@linux.ibm.com Cc: Yang Jihong yangjihong1@huawei.com Link: https://lore.kernel.org/r/20211228111338.218602-1-chenzechuan1@huawei.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index b2a02c9ab8ea..a834918a0a0d 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -3083,6 +3083,9 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, for (j = 0; j < num_matched_functions; j++) { sym = syms[j];
+ if (sym->type != STT_FUNC) + continue; + /* There can be duplicated symbols in the map */ for (i = 0; i < j; i++) if (sym->start == syms[i]->start) {