Messages in this thread Patch in this message | | | From | Arnaldo Carvalho de Melo <> | Subject | [PATCH 3/9] perf annotate browser: Be more robust when drawing jump arrows | Date | Tue, 6 Mar 2018 14:23:37 -0300 |
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From: Arnaldo Carvalho de Melo <acme@redhat.com>
This first happened with a gcc function, _cpp_lex_token, that has the usual jumps:
│1159e6c: ↓ jne 115aa32 <_cpp_lex_token@@Base+0xf92>
I.e. jumps to a label inside that function (_cpp_lex_token), and those works, but also this kind:
│1159e8b: ↓ jne c469be <cpp_named_operator2name@@Base+0xa72>
I.e. jumps to another function, outside _cpp_lex_token, which are not being correctly handled generating as a side effect references to ab->offset[] entries that are set to NULL, so to make this code more robust, check that here.
A proper fix for will be put in place, looking at the function name right after the '<' token and probably treating this like a 'call' instruction.
For now just don't draw the arrow.
Reported-by: Ingo Molnar <mingo@kernel.org> Tested-by: Ingo Molnar <mingo@kernel.org> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Cc: Jin Yao <yao.jin@intel.com> Cc: Kan Liang <kan.liang@intel.com> Link: https://lkml.kernel.org/n/tip-5tzvb875ep2sel03aeefgmud@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> --- tools/perf/ui/browsers/annotate.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)
diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c index 286427975112..fbf927cf775d 100644 --- a/tools/perf/ui/browsers/annotate.c +++ b/tools/perf/ui/browsers/annotate.c @@ -327,7 +327,32 @@ static void annotate_browser__draw_current_jump(struct ui_browser *browser) if (!disasm_line__is_valid_jump(cursor, sym)) return; + /* + * This first was seen with a gcc function, _cpp_lex_token, that + * has the usual jumps: + * + * │1159e6c: ↓ jne 115aa32 <_cpp_lex_token@@Base+0xf92> + * + * I.e. jumps to a label inside that function (_cpp_lex_token), and + * those works, but also this kind: + * + * │1159e8b: ↓ jne c469be <cpp_named_operator2name@@Base+0xa72> + * + * I.e. jumps to another function, outside _cpp_lex_token, which + * are not being correctly handled generating as a side effect references + * to ab->offset[] entries that are set to NULL, so to make this code + * more robust, check that here. + * + * A proper fix for will be put in place, looking at the function + * name right after the '<' token and probably treating this like a + * 'call' instruction. + */ target = ab->offsets[cursor->ops.target.offset]; + if (target == NULL) { + ui_helpline__printf("WARN: jump target inconsistency, press 'o', ab->offsets[%#x] = NULL\n", + cursor->ops.target.offset); + return; + } bcursor = browser_line(&cursor->al); btarget = browser_line(target); -- 2.14.3
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