(gdb) bt
#0  0x080ccaf6 in p2p_rtp_callback (id=0x823241c, fd=21, events=1, cbdata=0x82f0b9c) at rtp.c:2935
#1  0x080a47f8 in ast_io_wait (ioc=0x81ccbdc, howlong=470) at io.c:279
#2  0xb73ce693 in do_monitor (data=0x0) at chan_sip.c:15071
#3  0x080f2ac4 in dummy_start (data=0x81cf0c4) at utils.c:545
#4  0xb7d6b34b in start_thread () from /lib/libpthread.so.0
#5  0xb7b9865e in clone () from /lib/libc.so.6
(gdb) bt full
#0  0x080ccaf6 in p2p_rtp_callback (id=0x823241c, fd=21, events=1, cbdata=0x82f0b9c) at rtp.c:2935
        res = 172
        hdrlen = 12
        sin = {sin_family = 2, sin_port = 32838, sin_addr = {s_addr = 63434064}, sin_zero = "\000\000\000\000\000\000\000"}
        len = 16
        header = (unsigned int *) 0x82f0c20
        rtp = (struct ast_rtp *) 0x82f0b9c
        is_rtp = 0
        is_rtcp = 0
        __PRETTY_FUNCTION__ = "p2p_rtp_callback"
#1  0x080a47f8 in ast_io_wait (ioc=0x81ccbdc, howlong=470) at io.c:279
        res = 11
        x = 12
        origcnt = 21
#2  0xb73ce693 in do_monitor (data=0x0) at chan_sip.c:15071
        res = 470
        dialog = (struct sip_pvt *) 0x0
        peer = (struct sip_peer *) 0x0
        t = 1165851244
        fastrestart = 0
        lastpeernum = -1
        curpeernum = 0
        reloading = 0
        __PRETTY_FUNCTION__ = "do_monitor"
#3  0x080f2ac4 in dummy_start (data=0x81cf0c4) at utils.c:545
        __cancel_buf = {__cancel_jmp_buf = {{__cancel_jmp_buf = {-1210617868, 0, 0, -1221237656, -1420622416, 342444836}, __mask_was_saved = 0}}, __pad = {
    0xb73564a0, 0x0, 0x0, 0x0}}
        __cancel_routine = (void (*)(void *)) 0x8069168 <ast_unregister_thread>
        __cancel_arg = (void *) 0xb7356ba0
        not_first_call = 0
        ret = (void *) 0x0
        a = {start_routine = 0xb73ce460 <do_monitor>, data = 0x0,
  name = 0x81cf13c "do_monitor", ' ' <repeats 11 times>, "started at [15130] chan_sip.c restart_monitor()"}
        __PRETTY_FUNCTION__ = "dummy_start"
#4  0xb7d6b34b in start_thread () from /lib/libpthread.so.0
No symbol table info available.
#5  0xb7b9865e in clone () from /lib/libc.so.6
No symbol table info available.