From: Victor Kamensky <[email protected]> After commit 5baecbcd9c9a ("perf symbols: we can now read separate debug-info files based on a build ID") and when --symfs option is used perf failed to pick up symbols for file with the same name between host and sysroot specified by --symfs option. One can see message like this:
bin/bash with build id 26f0062cb6950d4d1ab0fd9c43eae8b10ca42062 not found, continuing without symbols It happens because code added by 5baecbcd9c9a opens files directly by dso->long_name without symbol_conf.symfs consideration, which as result picks one from the host. It reads its build ID and later even code finds another proper file in directory pointed by --symfs perf ignores it because build id mismatches. Fix is to use __symbol__join_symfs to adjust file name according to --symfs setting. If no --symfs passed the operation would noop and picks the same host file as before. Also note in latter tree after 5baecbcd9c9a commit additional check for '!dso->has_build_id' was added, so to observe error condition 'perf record' should run with --no-buildid, so perf.data itself would not have build id for target binary in buildid perf section and 'perf report' will pass '!dso->has_build_id' condition. Or target binary should not have build id, but the same binary on host has build id, again '!dso->has_build_id' will pass in this case and incorrect build id could be read if --symfs is used. Signed-off-by: Victor Kamensky <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Chris Phlipot <[email protected]> Cc: Dima Kogan <[email protected]> Cc: He Kuang <[email protected]> Cc: Kan Liang <[email protected]> Cc: Masami Hiramatsu <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Wang Nan <[email protected]> Cc: [email protected] Fixes: 5baecbcd9c9a ("perf symbols: we can now read separate debug-info files based on a build ID") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/symbol.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index dc93940de351..70e389bc4af7 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1460,9 +1460,11 @@ int dso__load(struct dso *dso, struct map *map) * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work */ if (!dso->has_build_id && - is_regular_file(dso->long_name) && - filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0) + is_regular_file(dso->long_name)) { + __symbol__join_symfs(name, PATH_MAX, dso->long_name); + if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0) dso__set_build_id(dso, build_id); + } /* * Iterate over candidate debug images. -- 2.9.3

