Hi Greg, There's a bit more fallout from pulling in the patches we discussed in this thread: https://lkml.org/lkml/2017/7/5/537 While those patches fixed the build, I didn't get a chance to run a full set of tests on the result. Last week, when attempting to set a kretprobe in a kernel module using 'perf probe' I hit an assertion that triggers when you attempt to delete an object that's still in a tree. It turned out that the patch below was also pushed around the same time as the others that had been pulled into 4.9, and so we'd missed a case where a refcount was not getting correctly incremented. The patch below is just a git cherry-pick of the commit from HEAD to the stable 4.9 branch. This addressed the refcount assertion failure I was seeing. Thanks, -K ------------------------------------------------- From: Masami Hiramatsu <mhiramat@xxxxxxxxxx> commit eebc509b20881b92d62e317b2c073e57c5f200f0 upstream. Fix --funcs (-F) option to show correct symbols for offline module. Since previous perf-probe uses machine__findnew_module_map() for offline module, even if user passes a module file (with full path) which is for other architecture, perf-probe always tries to load symbol map for current kernel module. This fix uses dso__new_map() to load the map from given binary as same as a map for user applications. Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Link: http://lkml.kernel.org/r/148350053478.19001.15435255244512631545.stgit@devbox Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/util/probe-event.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 6c50d9f..b7c7f42 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -163,7 +163,7 @@ static struct map *kernel_get_module_map(const char *module) /* A file path -- this is an offline module */ if (module && strchr(module, '/')) - return machine__findnew_module_map(host_machine, 0, module); + return dso__new_map(module); if (!module) module = "kernel"; @@ -173,6 +173,7 @@ static struct map *kernel_get_module_map(const char *module) if (strncmp(pos->dso->short_name + 1, module, pos->dso->short_name_len - 2) == 0 && module[pos->dso->short_name_len - 2] == '\0') { + map__get(pos); return pos; } } @@ -188,15 +189,6 @@ struct map *get_target_map(const char *target, bool user) return kernel_get_module_map(target); } -static void put_target_map(struct map *map, bool user) -{ - if (map && user) { - /* Only the user map needs to be released */ - map__put(map); - } -} - - static int convert_exec_to_group(const char *exec, char **result) { char *ptr1, *ptr2, *exec_copy; @@ -412,7 +404,7 @@ static int find_alternative_probe_point(struct debuginfo *dinfo, } out: - put_target_map(map, uprobes); + map__put(map); return ret; } @@ -2944,7 +2936,7 @@ static int find_probe_trace_events_from_map(struct perf_probe_event *pev, } out: - put_target_map(map, pev->uprobes); + map__put(map); free(syms); return ret; -- 2.10.1 (Apple Git-78)