On 01/26/2012 01:08 PM, Tanu Kaskinen wrote: > On Thu, 2012-01-26 at 12:35 +0100, David Henningsson wrote: >> I'm trying to trace down a memory error in module-dbus-protocol, but I >> am confused. >> >> Either you use synchronous hooks, and then you can reference the >> original core objects, or you use asynchronous subscription events, in >> which case the pointers can become dangling at any time, so you can't >> point into the core and have to make memory copies of *everything*. Right? > > Make copies, or check if the objects are still in the core before > referencing them. I tried to make those checks where needed, but > apparently I failed at that. > >> The card is handled by subscription events, and I get memory errors on >> quit [1] due to it referencing the profile's name as a hash key (!). But >> while investigating I also saw pa_dbusiface_card_profile objects having >> a pointer to the profile, which is disturbing. >> >> If this is the only place where things are broken, I can fix it. But if >> the same logic faults apply to all over the dbus protocol module, that >> makes me quite uneasy with shipping it in a stable distribution, >> especially as I don't know any consumer that makes use of this information. > > Now that you've pointed out this issue, I don't trust the code at all > anymore. The only sane way forward is to convert all code in the dbus > module to use hooks instead of the subscription system. > > I volunteer to do that work. FYI, for the reasons above, module-dbus-protocol has now been disabled in the upcoming release of Ubuntu, 12.04. We just commented the line out in /etc/pulse/default.pa so it's easy to re-enable. (Btw, the only known user of module-dbus-protocol is qpaeq, which Ubuntu does not currently ship.) -- David Henningsson, Canonical Ltd. http://launchpad.net/~diwic
