segmentation fault when scanning channels for DVB

[glemsom@…]

mythtv-setup is unable to scan for DVB-C channels - and causes a segmentation fault. Steps:

1. Close mythbackend.
2. Start mythtv-setup
3. Configure DVB-C card and some video-source (no grabber)
4. Goto Input connections - and assosiate the video-source.
5. Select "Full Scan of Existing Transports" or Full Scan (I ised: Freq: 143000000, Symbolrate: 6875000)

Hit "Next" and mythtv-setup will cause a segmentation fault

[charles]

I can confirm. I'll try to debug.

[charles]

I'm running Ubuntu 8.10, with mythtv 0.21+fixes 18722. I recompiled with debug symbols.

The attached gdb output is generated after scanning a known transport for channels (using DVB-C). Scan works perfect, updates are processed, but the usual 'Finish' screen crashes/segfaults.

More information needed?

[charles]

gdb output of transport scan

[development@…]

I think this problem is related to multiple core cpu.

With "taskset -c 0 mythtv-setup" (running only on the first cpu core) dvb scan ends without errors.

Note: It appear both on DVB-S and DVB-T. Note2: At the moment I cannot reproduce it...

[danielk]

This segfault doesn't happen with the new scanner in the mythtv-channel-scan branch, and I've tried unsuccessfully to fix it with the old scanner one too many times, so this is a wontfix. As soon as the issues with the new scanner wrt to DVB-X are resolved we'll replace the current non-thread-safe scanner with the new thread-safe channel scanner...