From: Wang Nan [mailto:wangn...@huawei.com] > >It is possible that find_perf_probe_point_from_map() fails to find >symbol but still returns 0 because of an small error when coding: >find_perf_probe_point_from_map() set 'ret' to error code at first, >but also use it to hold return value of >kernel_get_symbol_address_by_name().
OK, I didn't expect that there is a symbol which can be found by kernel_get_symbol_address_by_name() but not by __find_kernel_function()... Would you have any example of the error? > >This patch resets 'ret' to error even kernel_get_symbol_address_by_name() >success, so if !sym, the whole function returns error correctly. Hmm, that sounds tricky. I'd rather like to add *psym to kernel_get_symbol_address_by_name() to save symbol and don't use __find_kernel_function() instead. Thank you, > >Signed-off-by: Wang Nan <wangn...@huawei.com> >Cc: Arnaldo Carvalho de Melo <a...@redhat.com> >Cc: Jiri Olsa <jo...@kernel.org> >Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> >Cc: Namhyung Kim <namhy...@kernel.org> >--- > tools/perf/util/probe-event.c | 3 +++ > 1 file changed, 3 insertions(+) > >diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c >index b51a8bf..e659c4f 100644 >--- a/tools/perf/util/probe-event.c >+++ b/tools/perf/util/probe-event.c >@@ -1905,6 +1905,9 @@ static int find_perf_probe_point_from_map(struct >probe_trace_point *tp, > sym = __find_kernel_function(addr, &map); > } > } >+ >+ /* ret may has be overwritten so reset it */ >+ ret = -ENOENT; > if (!sym) > goto out; > >-- >1.8.3.4
