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author | Thomas Richter <tmricht@linux.ibm.com> | 2018-05-28 09:36:57 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-08 15:30:52 +0200 |
commit | be5af6bec31a5c22f61de1be848c3fd0e6e3a2f8 (patch) | |
tree | ec9a6984f6ff4a4e52c90da3badfa0e02d7f133c /tools/perf | |
parent | d689ad5c91af0843aceef7975d7ca9356c84a335 (diff) | |
download | linux-stable-be5af6bec31a5c22f61de1be848c3fd0e6e3a2f8.tar.gz linux-stable-be5af6bec31a5c22f61de1be848c3fd0e6e3a2f8.tar.bz2 linux-stable-be5af6bec31a5c22f61de1be848c3fd0e6e3a2f8.zip |
perf test: "Session topology" dumps core on s390
[ Upstream commit d121109100bda84bbbb199dab97f9d56432ab235 ]
The "perf test Session topology" entry fails with core dump on s390. The root
cause is a NULL pointer dereference in function check_cpu_topology() line 76
(or line 82 without -v).
The session->header.env.cpu variable is NULL because on s390 function
process_cpu_topology() returns with error:
socket_id number is too big.
You may need to upgrade the perf tool.
and releases the env.cpu variable via zfree() and sets it to NULL.
Here is the gdb output:
(gdb) n
76 pr_debug("CPU %d, core %d, socket %d\n", i,
(gdb) n
Program received signal SIGSEGV, Segmentation fault.
0x00000000010f4d9e in check_cpu_topology (path=0x3ffffffd6c8
"/tmp/perf-test-J6CHMa", map=0x14a1740) at tests/topology.c:76
76 pr_debug("CPU %d, core %d, socket %d\n", i,
(gdb)
Make sure the env.cpu variable is not used when its NULL.
Test for NULL pointer and return TEST_SKIP if so.
Output before:
[root@p23lp27 perf]# ./perf test -F 39
39: Session topology :Segmentation fault (core dumped)
[root@p23lp27 perf]#
Output after:
[root@p23lp27 perf]# ./perf test -vF 39
39: Session topology :
--- start ---
templ file: /tmp/perf-test-Ajx59D
socket_id number is too big.You may need to upgrade the perf tool.
---- end ----
Session topology: Skip
[root@p23lp27 perf]#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20180528073657.11743-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/perf')
-rw-r--r-- | tools/perf/tests/topology.c | 30 |
1 files changed, 24 insertions, 6 deletions
diff --git a/tools/perf/tests/topology.c b/tools/perf/tests/topology.c index a59db7c45a65..81ede20f49d7 100644 --- a/tools/perf/tests/topology.c +++ b/tools/perf/tests/topology.c @@ -66,6 +66,27 @@ static int check_cpu_topology(char *path, struct cpu_map *map) session = perf_session__new(&file, false, NULL); TEST_ASSERT_VAL("can't get session", session); + /* On platforms with large numbers of CPUs process_cpu_topology() + * might issue an error while reading the perf.data file section + * HEADER_CPU_TOPOLOGY and the cpu_topology_map pointed to by member + * cpu is a NULL pointer. + * Example: On s390 + * CPU 0 is on core_id 0 and physical_package_id 6 + * CPU 1 is on core_id 1 and physical_package_id 3 + * + * Core_id and physical_package_id are platform and architecture + * dependend and might have higher numbers than the CPU id. + * This actually depends on the configuration. + * + * In this case process_cpu_topology() prints error message: + * "socket_id number is too big. You may need to upgrade the + * perf tool." + * + * This is the reason why this test might be skipped. + */ + if (!session->header.env.cpu) + return TEST_SKIP; + for (i = 0; i < session->header.env.nr_cpus_avail; i++) { if (!cpu_map__has(map, i)) continue; @@ -91,7 +112,7 @@ int test__session_topology(struct test *test __maybe_unused, int subtest __maybe { char path[PATH_MAX]; struct cpu_map *map; - int ret = -1; + int ret = TEST_FAIL; TEST_ASSERT_VAL("can't get templ file", !get_temp(path)); @@ -106,12 +127,9 @@ int test__session_topology(struct test *test __maybe_unused, int subtest __maybe goto free_path; } - if (check_cpu_topology(path, map)) - goto free_map; - ret = 0; - -free_map: + ret = check_cpu_topology(path, map); cpu_map__put(map); + free_path: unlink(path); return ret; |