[mythtv] 0.21 Firewire bus reset every 60 seconds?

[Derek Atkins]

Hi,

I was watching the backend logs during the recording of BBC World News
this morning and noticed that it performed a pair of bus resets every
60 seconds.  Watching the video now (an hour later) I notice a
video/audio glitch every 60 seconds, but no particular other issues.
I don't recall having this level of firewire issue when I was running
0.20.

Here's an example of the backend log between the 60-second "okay period":

2008-06-11 08:43:37.498 LFireDev(000E5CFFFE5AF9A5): SignalReset(86->87)
2008-06-11 08:43:37.553 LFireDev(000E5CFFFE5AF9A5): SignalReset(86->87): Updating device list -- begin
2008-06-11 08:43:37.815 LFireDev(000E5CFFFE5AF9A5): SignalReset(86->87): Updating device list -- end
2008-06-11 08:43:37.917 LFireDev(000E5CFFFE5AF9A5), Warning: No Input in 50 msec...
2008-06-11 08:44:37.501 LFireDev(000E5CFFFE5AF9A5), Warning: No Input in 100 msec...

In the system logs I do see some instances of:

Jun 11 08:21:57 myth-frontend0 kernel: ohci1394: fw-host0: IR DMA error - OHCI error code 0x1d
Jun 11 08:21:57 myth-frontend0 kernel: 
Jun 11 08:27:23 myth-frontend0 kernel: ohci1394: fw-host0: IR DMA error - OHCI error code 0x1d

But the timestamps do not correspond at all to the bus resets.

Without looking at the code it LOOKS like there's a 60 second timer
that doesn't get reset properly once the firewire is working properly.

And then, of course, the backend died of a SEGV (sorry, no crash
dump) during a reset:

2008-06-11 08:44:52.108 LFireDev(000E5CFFFE5AF9A5): ResetBus() -- begin
2008-06-11 08:44:52.220 LFireDev(000E5CFFFE5AF9A5): ResetBus() -- end
2008-06-11 08:44:52.324 LFireDev(000E5CFFFE5AF9A5): SignalReset(91->92)
2008-06-11 08:44:52.429 LFireDev(000E5CFFFE5AF9A5): SignalReset(91->92): Updating device list -- begin
2008-06-11 08:44:52.844 LFireDev(000E5CFFFE5AF9A5): SignalReset(91->92): Updating device list -- end

and

Jun 11 08:45:04 myth-frontend0 kernel: mythbackend[4904]: segfault at 00002aaab4856000 rip 000000363767709c rsp 000000004960da68 error 4

-derek

-- 
       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
       warlord at MIT.EDU                        PGP key available