summaryrefslogtreecommitdiff
path: root/tools
diff options
context:
space:
mode:
authorJiri Olsa <jolsa@kernel.org>2018-02-15 13:26:35 +0100
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2018-05-30 07:50:50 +0200
commitf97276ccfd66b11da8948271b052f5e4226a47a1 (patch)
treea7f0330d449ab860b56b216a7da1b63ce29d3121 /tools
parent1e6b708a1dc617478a6dede5ecd38e055f3b1e35 (diff)
perf tests: Use arch__compare_symbol_names to compare symbols
[ Upstream commit ab6e9a99345131cd8e54268d1d0dc04a33f7ed11 ] The symbol search called by machine__find_kernel_symbol_by_name is using internally arch__compare_symbol_names function to compare 2 symbol names, because different archs have different ways of comparing symbols. Mostly for skipping '.' prefixes and similar. In test 1 when we try to find matching symbols in kallsyms and vmlinux, by address and by symbol name. When either is found we compare the pair symbol names by simple strcmp, which is not good enough for reasons explained in previous paragraph. On powerpc this can cause lockup, because even thought we found the pair, the compared names are different and don't match simple strcmp. Following code path is executed, that leads to lockup: - we find the pair in kallsyms by sym->start next_pair: - we compare the names and it fails - we find the pair by sym->name - the pair addresses match so we call goto next_pair because we assume the names match in this case Signed-off-by: Jiri Olsa <jolsa@kernel.org> Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: 031b84c407c3 ("perf probe ppc: Enable matching against dot symbols automatically") Link: http://lkml.kernel.org/r/20180215122635.24029-10-jolsa@kernel.org 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')
-rw-r--r--tools/perf/tests/vmlinux-kallsyms.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c
index a5082331f246..2aabf0ae7c0d 100644
--- a/tools/perf/tests/vmlinux-kallsyms.c
+++ b/tools/perf/tests/vmlinux-kallsyms.c
@@ -123,7 +123,7 @@ int test__vmlinux_matches_kallsyms(int subtest __maybe_unused)
if (pair && UM(pair->start) == mem_start) {
next_pair:
- if (strcmp(sym->name, pair->name) == 0) {
+ if (arch__compare_symbol_names(sym->name, pair->name) == 0) {
/*
* kallsyms don't have the symbol end, so we
* set that by using the next symbol start - 1,