Re: perf seg fault

From: Jiri Olsa
Date: Tue May 12 2020 - 11:10:59 EST


On Tue, May 12, 2020 at 05:58:29PM +0300, Adrian Hunter wrote:
> Forgot to cc mailing list
>
> On 12/05/20 5:50 pm, Adrian Hunter wrote:
> > Hi
> >
> > I am getting a seg fault from your perf/core branch, as follows:
> >
> > # perf record uname
> > Linux
> > [ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 0.005 MB perf.data (7 samples) ]
> > perf: Segmentation fault
> > Obtained 6 stack frames.
> > [0x4e75b4]
> > [0x5d1ad0]
> > [0x5c9860]
> > [0x4a6e5c]
> > [0x5cb39b]
> > [0x76c89f]
> > Segmentation fault
> >
> > It goes away with --no-bpf-event:
> >
> > # perf record --no-bpf-event uname
> > Linux
> > [ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 0.005 MB perf.data (7 samples) ]
> > #
> >
> > kernel is from the same branch
> >
> > # uname -a
> > Linux buildroot 5.7.0-rc2-00028-g0fdddf5a583a #165 SMP Tue May 12 16:27:53
> > EEST 2020 x86_64 GNU/Linux
> >
> > # perf version --build-options
> > perf version 5.6.g0fdddf5a583a
> > dwarf: [ OFF ] # HAVE_DWARF_SUPPORT
> > dwarf_getlocations: [ OFF ] # HAVE_DWARF_GETLOCATIONS_SUPPORT
> > glibc: [ on ] # HAVE_GLIBC_SUPPORT
> > gtk2: [ OFF ] # HAVE_GTK2_SUPPORT
> > syscall_table: [ on ] # HAVE_SYSCALL_TABLE_SUPPORT
> > libbfd: [ on ] # HAVE_LIBBFD_SUPPORT
> > libelf: [ on ] # HAVE_LIBELF_SUPPORT
> > libnuma: [ OFF ] # HAVE_LIBNUMA_SUPPORT
> > numa_num_possible_cpus: [ OFF ] # HAVE_LIBNUMA_SUPPORT
> > libperl: [ OFF ] # HAVE_LIBPERL_SUPPORT
> > libpython: [ OFF ] # HAVE_LIBPYTHON_SUPPORT
> > libslang: [ on ] # HAVE_SLANG_SUPPORT
> > libcrypto: [ on ] # HAVE_LIBCRYPTO_SUPPORT
> > libunwind: [ OFF ] # HAVE_LIBUNWIND_SUPPORT
> > libdw-dwarf-unwind: [ OFF ] # HAVE_DWARF_SUPPORT
> > zlib: [ OFF ] # HAVE_ZLIB_SUPPORT
> > lzma: [ OFF ] # HAVE_LZMA_SUPPORT
> > get_cpuid: [ on ] # HAVE_AUXTRACE_SUPPORT
> > bpf: [ OFF ] # HAVE_LIBBPF_SUPPORT
> > aio: [ on ] # HAVE_AIO_SUPPORT
> > zstd: [ OFF ] # HAVE_ZSTD_SUPPORT
> >
> >
> > Any thoughts?

hum, I don't see that, do you reproduce with DEBUG=1?
to get more verbose backtrace

jirka