[mythtv] more on dvb record failure (race condition in signalmonitor.cpp?)

[Mark Weaver]

Mark Weaver wrote:
> I am also having trouble with DVB (livetv|recording) -- sometimes 
> getting the PMT timeout.  I have tried latest SVN but the backend seems 
> very unstable for me.  I've done a little debugging, so far I think I 
> have found a race condition in signalmonitor.cpp:
Hmm, ok maybe that's not true, gdb thinks exit=false,update_rate=0,etc. 
  I've also managed to get it to SIGSEGV as below.  Any ideas?  Botched 
compile somehow?


Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1363731536 (LWP 31205)]
0xb6392887 in mallopt () from /lib/tls/libc.so.6
(gdb) bt
#0  0xb6392887 in mallopt () from /lib/tls/libc.so.6
#1  0xb6391c43 in malloc () from /lib/tls/libc.so.6
#2  0xb65132fe in operator new () from /usr/lib/libstdc++.so.5
#3  0xb6b069b3 in QMapPrivate<QString, Param>::QMapPrivate ()
    from /usr/lib/libqt-mt.so.3
#4  0xb6b05bc5 in QSqlExtension::QSqlExtension () from 
/usr/lib/libqt-mt.so.3
#5  0xb6b0782a in QSqlResult::QSqlResult () from /usr/lib/libqt-mt.so.3
#6  0xb59fca9c in QMYSQLResult::QMYSQLResult ()
    from /usr/lib/qt3/plugins/sqldrivers/libqsqlmysql.so
#7  0xb59fe86a in QMYSQLDriver::createQuery ()
    from /usr/lib/qt3/plugins/sqldrivers/libqsqlmysql.so
#8  0xb6af2a33 in QSqlQuery::init () from /usr/lib/libqt-mt.so.3
#9  0xb6af28e8 in QSqlQuery::QSqlQuery () from /usr/lib/libqt-mt.so.3
#10 0xb721f32e in MSqlQuery (this=0xaeb71780, qi=@0xaeb71770)
     at mythdbcon.cpp:207
#11 0xb7bc2747 in TVRec::SetVideoFiltersForChannel (this=0x810a120,
     chan=0x81109f8, channum=@0xaeb71910) at tv_rec.cpp:2478
#12 0xb7bb7e8e in TVRec::StartChannel (this=0x810a120, livetv=true)
     at tv_rec.cpp:1329
#13 0xb7bb3a17 in TVRec::StartRecorderPost (this=0x810a120,
     dummyrec=0x8123ac0, livetv=true) at tv_rec.cpp:778
#14 0xb7bb33f2 in TVRec::StartRecorderPostThunk (param=0x8121170)
     at tv_rec.cpp:726
---Type <return> to continue, or q <return> to quit---~
#15 0xb653fb63 in start_thread () from /lib/tls/libpthread.so.0
#16 0xb63f818a in clone () from /lib/tls/libc.so.6