Re: [PATCH v1 1/2] perf machine: Factor creating a "live" machine out of dwarf-unwind

[Arnaldo Carvalho de Melo <acme@kernel.org>]

On Fri, Mar 14, 2025 at 02:18:49PM -0300, Arnaldo Carvalho de Melo wrote:
> On Wed, Mar 12, 2025 at 10:29:51PM -0700, Ian Rogers wrote:
> > Factor out for use in places other than the dwarf unwinding tests for
> > libunwind.
> 
> Testing with another patchset being reviewed/tested, seems to work, if
> it showed the line number would be even better!

But it gets the lines, at least in this secoond attempt, after applying
Namhyungs fix for the previous problem (int16_t):

root@number:~# perf trace -e landlock_add_rule perf test -w landlock
perf: Segmentation fault
    #0 0x6698d0 in dump_stack debug.c:355
    #1 0x66994c in sighandler_dump_stack debug.c:367
    #2 0x7f784be95fd0 in __restore_rt libc.so.6[40fd0]
    #3 0x4d0e56 in trace__find_usable_bpf_prog_entry builtin-trace.c:3882
    #4 0x4cf3de in trace__init_syscalls_bpf_prog_array_maps builtin-trace.c:4040
    #5 0x4bf626 in trace__run builtin-trace.c:4477
    #6 0x4bb7a9 in cmd_trace builtin-trace.c:5741
    #7 0x4d873f in run_builtin perf.c:351
    #8 0x4d7df3 in handle_internal_command perf.c:404
    #9 0x4d860f in run_argv perf.c:451
    #10 0x4d7a4f in main perf.c:558
    #11 0x7f784be7f088 in __libc_start_call_main libc.so.6[2a088]
    #12 0x7f784be7f14b in __libc_start_main@@GLIBC_2.34 libc.so.6[2a14b]
    #13 0x410ff5 in _start perf[410ff5]
Segmentation fault (core dumped)
root@number:~# 
 
> I'll continue working on that other case with this applied just before
> that series and finally will give my Tested-by.
> 
> - Arnaldo
> 
> root@number:~# perf trace -e landlock_add_rule perf test -w landlock
> perf: Segmentation fault
>     #0 0x5be81d in dump_stack perf[5be81d]
>     #1 0x5be879 in sighandler_dump_stack perf[5be879]
>     #2 0x7f313d24efd0 in __restore_rt libc.so.6[40fd0]
>     #3 0x491bc1 in cmd_trace perf[491bc1]
>     #4 0x497090 in run_builtin perf.c:0
>     #5 0x4973ab in handle_internal_command perf.c:0
>     #6 0x413483 in main perf[413483]
>     #7 0x7f313d238088 in __libc_start_call_main libc.so.6[2a088]
>     #8 0x7f313d23814b in __libc_start_main@@GLIBC_2.34 libc.so.6[2a14b]
>     #9 0x413ad5 in _start perf[413ad5]
> Segmentation fault (core dumped)
> root@number:~#