[mythtv] Crash in dvbdev/transform.c

[Jesper Sörensen]

I'm having some odd problems with DVB in MythTV, mainly regarding 
channel switching (frontend freezes waiting for data & sometimes backend 
crashes). There are probably a couple of different issues involved but 
you've got to start somewhere...

I got this backtrace from a crash earlier this evening. I thought I 
saved more of it but it seems I only got the top part. Let me know if 
it's not enough and I'll try to get another trace.

IIRC, the lower part of the backtrace was full of calls to write_ipack 
so it seems there was some heavy recursion going on. Is this normal? 
Could it be stack overflow causing this?


[Myth 0.15, source from Debian pkgs]

2004-05-31 17:58:33 Found changes in the todo list.
2004-05-31 17:58:33 Scheduled 3 items in 0.01571 seconds.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1221794736 (LWP 2838)]
0x403b6382 in ps_pes (p=0x80f8d18) at dvbdev/transform.c:1945
1945    {
Current language:  auto; currently c
(gdb) thread apply all bt full

Thread 17 (Thread 1221794736 (LWP 2838)):
#0  0x403b6382 in ps_pes (p=0x80f8d18) at dvbdev/transform.c:1945
        check = 1077633927
        pbuf = '\0' <repeats 31 times>
        SCR = 0
        pv = (ipack *) 0x0
        pa = (ipack *) 0x0
#1  0x403b6918 in send_ipack (p=0x80f8d18) at dvbdev/transform.c:2046
        streamid = 0
        off = 0
        ac3_off = 0
        ai = {layer = 0, bit_rate = 135236888, frequency = 135236888, 
mode = 0,
  mode_extension = 0, emphasis = 0, framesize = 0, off = 0}
        nframes = 0
        f = 0
#2  0x403b6d50 in write_ipack (p=0x80f8d18,
    data=0x80f6ab2 "o\026oi7j¹è\001\221 ³Å\005ÿ¿Ò", count=166)
    at dvbdev/transform.c:2123
        rest = 0
        ai = {layer = 0, bit_rate = 0, frequency = 0, mode = 0, 
mode_extension = 0,
---Type <return> to continue, or q <return> to quit---
  emphasis = 0, framesize = 0, off = 0}
        headr = "\000\000\001"
        diff = 60038
#3  0x403b6d7d in write_ipack (p=0x80f8d18,
    data=0x80f6ab2 "o\026oi7j¹è\001\221 ³Å\005ÿ¿Ò", count=166)
    at dvbdev/transform.c:2125
        rest = 0
        ai = {layer = 0, bit_rate = 0, frequency = 0, mode = 0, 
mode_extension = 0,
  emphasis = 0, framesize = 0, off = 0}
        headr = "\000\000\001"
        diff = 60038
#4  0x403b6d7d in write_ipack (p=0x80f8d18,
    data=0x80f6ab2 "o\026oi7j¹è\001\221 ³Å\005ÿ¿Ò", count=166)
    at dvbdev/transform.c:2125
        rest = 0
        ai = {layer = 0, bit_rate = 0, frequency = 0, mode = 0, 
mode_extension = 0,
  emphasis = 0, framesize = 0, off = 0}
        headr = "\000\000\001"
        diff = 60038
#5  0x403b6d7d in write_ipack (p=0x80f8d18,
    data=0x80f6ab2 "o\026oi7j¹è\001\221 ³Å\005ÿ¿Ò", count=166)