Re: perf mem report segfaulting

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

Em Mon, Aug 31, 2015 at 10:19:57AM +0200, Jiri Olsa escreveu:
> On Fri, Aug 28, 2015 at 02:04:14PM -0300, Arnaldo Carvalho de Melo wrote:
> > 
> > Hi,
> > 
> > 	While trying to test my tmp.perf/ui_browser.horiz_scroll branch
> > with 'perf mem report' to allow that kind of browsing on the TUI, as of
> > now it works only on --stdio mode, using the right/left arrow keys, I
> > noticed this in acme/perf/core (but I saw it too in many previous
> > revisions, trying to bisect it):
> > 
> > [root@zoo ~]# perf mem record -a
> > ^C[ perf record: Woken up 1 times to write data ]
> > [ perf record: Captured and wrote 3.072 MB perf.data (647 samples) ]
> > 
> > [root@zoo ~]# perf mem report
> > perf: Segmentation fault
> > -------- backtrace --------
> > perf[0x52a08b]
> > /lib64/libc.so.6(+0x34960)[0x7f8726860960]
> > perf(addr_map_symbol__inc_samples+0xbb)[0x47abfb]
> > perf[0x42e93f]
> > perf(hist_entry_iter__add+0x102)[0x4d9632]
> > perf[0x42e7ba]
> > perf[0x4bc4c3]
> > perf[0x4bc9c1]
> > perf[0x4bf6b9]
> > perf(perf_session__process_events+0x390)[0x4be1b0]
> > perf(cmd_report+0x1038)[0x42faf8]
> > perf(cmd_mem+0x3ec)[0x44c69c]
> > perf[0x479113]
> > perf(main+0x60a)[0x420a5a]
> > /lib64/libc.so.6(__libc_start_main+0xf0)[0x7f872684bfe0]
> > perf[0x420b79]
> > [0x0]
> > [root@zoo ~]# perf evlist
> > cpu/mem-loads/pp
> > cpu/mem-stores/pp
> > [root@zoo ~]#
> > 
> > Have you noticed this? No time to look at this now :-\
> 
> cannot reproduce it on your perf/core.. did you navigate
> to anything specific to trigger it?

Nope, all I did is in the report, i.e. it segfaults straight away, right
after running 'perf mem report'.

Trying again, with what is in v4.2.0, i.e. upstream Linus, freshly built
(the tooling part, the kernel is a 4.2.0-rc one):

[root@zoo ~]# perf mem record -a
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 3.260 MB perf.data (953 samples) ]

[root@zoo ~]# perf mem report
perf: Segmentation fault
-------- backtrace --------
perf[0x510c6b]
/lib64/libc.so.6(+0x34960)[0x7f27d6ed9960]
perf(addr_map_symbol__inc_samples+0xbb)[0x477ebb]
perf[0x42d017]
perf(hist_entry_iter__add+0x102)[0x4d4072]
perf[0x42ceda]
perf[0x4b7713]
perf[0x4b7bd1]
perf[0x4ba899]
perf(perf_session__process_events+0x390)[0x4b9390]
perf(cmd_report+0xfc9)[0x42e199]
perf(cmd_mem+0x3ec)[0x44aa6c]
perf[0x4767c3]
perf(main+0x60a)[0x41f19a]
/lib64/libc.so.6(__libc_start_main+0xf0)[0x7f27d6ec4fe0]
perf[0x41f2b9]
[0x0]
[root@zoo ~]# perf --version
perf version 4.2.g64291f
[root@zoo ~]# uname -a
Linux zoo 4.2.0-rc5+ #1 SMP Tue Aug 4 16:55:11 BRT 2015 x86_64 x86_64
x86_64 GNU/Linux
[root@zoo ~]# cat /etc/fedora-release 
Fedora release 21 (Twenty One)
[root@zoo ~]#