[mythtv-users] DVD Playback crashing in 0.24-fixes -- workaround

[Mark Lord]

On 12-04-01 02:32 PM, Jim Stichnoth wrote:
> On Sun, Apr 1, 2012 at 11:19 AM, Mark Lord <mythtv at rtr.ca> wrote:
>>
>> The crashes happen with/without VDPAU, and there have been many tickets
>> (from others) reporting the issue, but no resolution.
>>
>> I suspect a race between MythDVDPlayer::GetBookmark() and other parts of the player.
>> Saving bookmarks doesn't seem to cause trouble, just retrieving the first one
>> on resume of playback.  This leads to internal heap corruption in libc++,
>> and then subsequent crashes in unrelated sections of code.
>>
>> The code there does seem simple enough.  Some experienced C++ eyeballs
>> ought to be able to spot the bug.
> 
> Mark,
> 
> I've seen several of these tickets, but I can't reproduce the crashing
> on my system (either because I'm running Master instead of 0.24, or
> more likely because of some difference on my system).  If you can
> reproduce the crash reliably, could you try running valgrind on it?
> Something like:
>     valgrind --leak-check=yes mythfrontend ...
> 
> If there is some kind of memory corruption going on, valgrind might
> find something interesting before the crash.


That's a thought.  I'll give it a try when I next get the chance.
Meanwhile, I did look at master, and there appears to be a whole
new ringbuffer class specifically for DVD playback.. so it is quite
possible that the bug got eliminated when that happened.
Which is encouraging.

But master isn't ready for prime time yet (compared with 0.24-fixes),
so that won't be a viable option here for various reasons
until the summer or so.

I'll see what valgrind spews out later today, hopefully.

Cheers