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charset="UTF-8" In maps__load_first(), take a reference to the first map and drop maps__lock(maps) before calling map__load() to avoid a read-to-write self-deadlock when loading kernel maps inserts extra trampoline maps. Fixes: e77b0236cd0c ("perf maps: Add maps__load_first()") Signed-off-by: Ian Rogers --- tools/perf/util/maps.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c index f808df2fe77b..7ca33e5218e7 100644 --- a/tools/perf/util/maps.c +++ b/tools/perf/util/maps.c @@ -1459,10 +1459,15 @@ int maps__merge_in(struct maps *kmaps, struct map *new_map) void maps__load_first(struct maps *maps) { - down_read(maps__lock(maps)); + struct map *first = NULL; + down_read(maps__lock(maps)); if (maps__nr_maps(maps) > 0) - map__load(maps__maps_by_address(maps)[0]); - + first = map__get(maps__maps_by_address(maps)[0]); up_read(maps__lock(maps)); + + if (first) { + map__load(first); + map__put(first); + } } -- 2.56.0.455.g6c5a503b38-goog