From: Adrian Hunter adrian.hunter@intel.com

Commit 1c5aae7710bb ("perf machine: Create maps for x86 PTI entry trampolines") revealed a problem with maps__find_symbol_by_name() that resulted in probes not being found e.g.

$ sudo perf probe xsk_mmap xsk_mmap is out of .text, skip it. Probe point 'xsk_mmap' not found. Error: Failed to add events.

maps__find_symbol_by_name() can optionally return the map of the found symbol. It can get the map wrong because, in fact, the symbol is found on the map's dso, not allowing for the possibility that the dso has more than one map. Fix by always checking the map contains the symbol.

Reported-by: Björn Töpel bjorn.topel@intel.com Signed-off-by: Adrian Hunter adrian.hunter@intel.com Tested-by: Björn Töpel bjorn.topel@intel.com Cc: Jiri Olsa jolsa@redhat.com Cc: stable@vger.kernel.org Fixes: 1c5aae7710bb ("perf machine: Create maps for x86 PTI entry trampolines") Link: http://lkml.kernel.org/r/20180907085116.25782-1-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com --- tools/perf/util/map.c | 11 +++++++++++ 1 file changed, 11 insertions(+)

diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index 36d0763311ef..6a6929f208b4 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -576,6 +576,13 @@ struct symbol *map_groups__find_symbol(struct map_groups *mg, return NULL; }

+static bool map__contains_symbol(struct map *map, struct symbol *sym) +{ + u64 ip = map->unmap_ip(map, sym->start); + + return ip >= map->start && ip < map->end; +} + struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name, struct map **mapp) { @@ -591,6 +598,10 @@ struct symbol *maps__find_symbol_by_name(struct maps *maps, const char *name,

if (sym == NULL) continue; + if (!map__contains_symbol(pos, sym)) { + sym = NULL; + continue; + } if (mapp != NULL) *mapp = pos; goto out;