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(a)lists.jackaudio.org http://lists.jackaudio.org/listinfo.cgi/jack-devel-jackaudio.org