Re: [PATCH v2] perf check: Add sanitizer feature and use to avoid test failure

[Namhyung Kim]

On Tue, Oct 22, 2024 at 11:18:18PM -0700, Namhyung Kim wrote:
> On Tue, Oct 22, 2024 at 10:39:36AM -0700, Ian Rogers wrote:
> > Sure, the reproduction is trivial, just add -fsanitize=address, so I'm
> > surprised you're not already seeing it:
> > ```
> > $ perf test annotate -v
> > --- start ---
> > test child forked, pid 444258
> >  68e8a0-68e96b l noploop
> > perf does have symbol 'noploop'
> > Basic perf annotate test
> >          : 0      0x68e8a0 <noploop>:
> >     0.00 :   68e8a0:       pushq   %rbp
> >     0.00 :   68e8a1:       movq    %rsp, %rbp
> >     0.00 :   68e8a4:       subq    $0x30, %rsp
[...]
> >     0.00 :   92d6:       shrl    %cl, %edx
> >     0.00 :   92d8:       movl    %edx, %ecx
> >     0.00 :   92da:       movq    %rax, %rdx
> > Basic annotate [Failed: missing disasm output when specifying the target symbol]
> 
> Hmm.. this is strange.  The error message says it failed when it
> specified the target symbol (noploop) for perf annotate.
> 
> As it's the dominant symbol, it should have the same output for the
> first function (noploop) whether it has target symbol or not and it
> should match the disasm_regex.  I'm curious how it can fail here.

Hmm.. ok.  For some reason, it wasn't failed when I add DEBUG=1.

Without DEBUG, I can see it now.

=================================================================
==1053492==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 33 byte(s) in 1 object(s) allocated from:
    #0 0x7f1ad78edd20 in strdup ../../../../src/libsanitizer/asan/asan_interceptors.cpp:566
    #1 0x55eda19cb76f in perf_data__open (linux/tools/perf/perf+0x65276f) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #2 0x55eda18ffafa in __perf_session__new (linux/tools/perf/perf+0x586afa) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #3 0x55eda15485d3 in cmd_annotate (linux/tools/perf/perf+0x1cf5d3) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #4 0x55eda1695467 in run_builtin (linux/tools/perf/perf+0x31c467) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #5 0x55eda1695c0e in handle_internal_command (linux/tools/perf/perf+0x31cc0e) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #6 0x55eda153ba72 in main (linux/tools/perf/perf+0x1c2a72) (BuildId: 6fc1b7cdc123c7bd586ce55ea8b727875f42cda2)
    #7 0x7f1acda43b89 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

SUMMARY: AddressSanitizer: 33 byte(s) leaked in 1 allocation(s).
Unexpected signal in test_basic

No idea how it can leak the data->file.path (that's what I can find
where strdup is used in the function).

Thanks,
Namhyung