[Jack-Devel] jack alsa midi segfault

[Paul Davis]

This is fixed in jack1 git. I really should get a release out there.

On the other hand, with that version of JACK, there's no excuse for using
-X seq anyway. It is terrible.

On Tue, Jun 23, 2015 at 10:42 AM, Tobias Hoffmann <
lfile-list at thax.hardliners.org> wrote:

> Hi,
>
> I using debian's
>   jackd version 0.124.1  tmpdir /dev/shm protocol 25
>
> started via
>   jackd -t1500 -dalsa -dhw:2 -r44100 -p128 -n4 -s -Xseq
> (or "jackd -Xalsa_midi ...")
>
> Then jackd segfaults shortly after
>   creating alsa_midi driver ...
> - every time, e.g:
>   jackd[25175]: segfault at 0 ip           (null) sp 00000000ffb828ac
> error 14 in jackd[8048000+5000]
>
> It does not segfault when -Xseq (-Xalsa_midi) is removed from the argument
> list.
> The very same invocation (same jackd version!) used to work until now, but
> I did update quite a few packages (e.g. libc, ...) in the mean time.
> I did try a reinstall of the jackd1-package, but it did not help.
> But I have not restarted the computer yet...
>
> Analysis:
> Starting jackd in gdb yields:
>
> Program received signal SIGSEGV, Segmentation fault.
> 0x00000000 in ?? ()
>
> without any backtrace left.
> But with some single-stepping I managed to get to this point:
>
> #0  0xf7f960d7 in jack_client_handle_latency_callback () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #1  0xf7f89466 in jack_deliver_event () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #2  0xf7f8b5ca in ?? () from /usr/lib/i386-linux-gnu/libjackserver.so.0
> #3  0xf7f8bec1 in jack_sort_graph () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #4  0xf7f8f792 in jack_client_activate () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #5  0xf7f8d662 in ?? () from /usr/lib/i386-linux-gnu/libjackserver.so.0
> #6  0xf7f8e50a in internal_client_request () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #7  0xf7f9563e in jack_client_deliver_request () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #8  0xf7f9868b in jack_activate () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #9  0xf6b47456 in ?? () from /usr/lib/i386-linux-gnu/jack/jack_alsa_midi.so
> #10 0xf7f88faa in jack_add_slave_driver () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #11 0xf7f89097 in jack_engine_load_slave_driver () from
> /usr/lib/i386-linux-gnu/libjackserver.so.0
> #12 0x0804a6d4 in ?? ()
> #13 0xf7bc8a63 in __libc_start_main
>
> The very next instruction crashes:
>   0xf7f960db <jack_client_handle_latency_callback+459>    call
>  *0x10f4(%eax)
> because *(eax+0x10f4)==0
>
> Starting jackd in valgrind:
> [...]
> ALSA: use 4 periods for playback
> creating alsa_midi driver ...
> ==25829== Conditional jump or move depends on uninitialised value(s)
> ==25829==    at 0x406EFAC: jack_client_handle_latency_callback (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4062465: jack_deliver_event (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x40645C9: ??? (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4064EC0: jack_sort_graph (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4068791: jack_client_activate (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4066661: ??? (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x1: ???
> ==25829==
> ==25829== Conditional jump or move depends on uninitialised value(s)
> ==25829==    at 0x406EFAC: jack_client_handle_latency_callback (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4062465: jack_deliver_event (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4064629: ??? (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4064EC0: jack_sort_graph (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4068791: jack_client_activate (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x4066661: ??? (in
> /usr/lib/i386-linux-gnu/libjackserver.so.0.0.28)
> ==25829==    by 0x1: ???
> ==25829==
>
> Does this make sense to anyone?
>
>   Tobias
> _______________________________________________
> Jack-Devel mailing list
> Jack-Devel at lists.jackaudio.org
> http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.linuxaudio.org/archives/jackaudio/attachments/20150623/69ff1210/attachment.html>