[Solved] LiveTV Segfault

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jiminorris
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[Solved] LiveTV Segfault

Post by jiminorris » Wed Jul 03, 2019 6:28 pm

I'm not sure if the -fixes branch pushed a mythbuntu repo update recently or not, but since rebooting my system this morning, LiveTV causes the frontend to crash. running with the -v switch gives this in the terminal:

Code: Select all

2019-07-03 19:16:50.422750 I  VDPAU: Added 2 output surfaces (total 4, max 4)
2019-07-03 19:16:59.940008 C  Received Segmentation fault: Code 1, PID 0, UID 0, Value 0x7f2f699e16d8
2019-07-03 19:17:00.040210 I  TV::StartTV(): Exiting main playback loop.
2019-07-03 19:17:00.154592 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.254744 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.354924 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.455110 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.555291 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.655498 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.755648 W  Player(0): Waited 100ms for decoder to pause
2019-07-03 19:17:00.855827 W  Player(0): Waited 100ms for decoder to pause
Segmentation fault (core dumped)
There's about 9.5 seconds of TV before the segfault. There';s nothing in the frontend or backend logs for this time period... Where do I start?

I'm using .30-fixes on 64bit LTS Ubuntu with the mythbuntu repository.

MikeB2013
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Re: LiveTV Segfault

Post by MikeB2013 » Wed Jul 03, 2019 8:29 pm

I am seeing a similar Segmentation fault, Live TV displays the channel for a few seconds then Seg faults.
It also Seg faults playing back a previously recorded program.

Would this be on BBC One channel (SD channel 1 not the HD channel on 101) by any chance ?
It seems that a recent change by broadcasters for Wimbledon more red button channels has upset mheg processing.
This could affect more than just BBC One

As a temporary workround try the following, it worked for me, on mythtv 29, 30 and current master frontends.

Mythfrontend Setup>Video>Playback OSD and uncheck Enable interactive TV

I really need to run a backtrace under gdb and submit a trac ticket, which I will do when I can get the time.


EDIT: track ticket created https://code.mythtv.org/trac/ticket/13467

Mike
Last edited by MikeB2013 on Thu Jul 04, 2019 8:22 am, edited 1 time in total.

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Steve Goodey
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Re: LiveTV Segfault

Post by Steve Goodey » Wed Jul 03, 2019 8:48 pm

Good catch, I'm getting that as well on v29, BBC1 SD only.
Last edited by Steve Goodey on Wed Jul 03, 2019 9:25 pm, edited 1 time in total.
Reason: Added BBC1 info.

shadowfirebird
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Re: LiveTV Segfault

Post by shadowfirebird » Wed Jul 03, 2019 8:56 pm

I'm seeing this across ALL BBC channels, even radio.

Or I was --- Mike's fix works perfectly.

I'd been tearing my hair out to fix the problem for Wimbledon week. Mike, I thank you; and my tennis-obsessed wife says thank you, too!

jiminorris
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Re: LiveTV Segfault

Post by jiminorris » Thu Jul 04, 2019 8:17 pm

MikeB2013 wrote:
Wed Jul 03, 2019 8:29 pm
I am seeing a similar Segmentation fault, Live TV displays the channel for a few seconds then Seg faults.
It also Seg faults playing back a previously recorded program.

Would this be on BBC One channel (SD channel 1 not the HD channel on 101) by any chance ?
It seems that a recent change by broadcasters for Wimbledon more red button channels has upset mheg processing.
This could affect more than just BBC One

As a temporary workround try the following, it worked for me, on mythtv 29, 30 and current master frontends.

Mythfrontend Setup>Video>Playback OSD and uncheck Enable interactive TV

I really need to run a backtrace under gdb and submit a trac ticket, which I will do when I can get the time.


EDIT: track ticket created https://code.mythtv.org/trac/ticket/13467

Mike

Yeah, BBC One, BBC2 and CBBC all affected, which is pretty much our entire live TV schedule!

Thanks for the workaround!

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