From ac8eb0581da2e7ef7faceba4947c393496d3a530 Mon Sep 17 00:00:00 2001 From: Robin Gareus Date: Sun, 12 Jan 2014 21:47:15 +0100 Subject: [PATCH] take process lock when adding processors: fixes possible crash if a processor modifies port-count 1. a processor is inserted and activated with processor-lock held 2. only after that the process_lock() is taken, configure_processors() is called which reconfigures-IO BUT if the processor that is inserted changes the channel count AND audio is processed before IOs are reconfigured -> possible crash (invalid port-buffers) To reproduce: Bus1 (2in, 3out), Bus2 (2in, 3out) - add a send from Bus1 to Bus2, - then add a processor to Bus1, just before the send which increases the channel-count to 4 -> occasional crash or assert. --- libs/ardour/route.cc | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libs/ardour/route.cc b/libs/ardour/route.cc index 4b9285c1c8..4171a9b239 100644 --- a/libs/ardour/route.cc +++ b/libs/ardour/route.cc @@ -947,6 +947,7 @@ Route::add_processor (boost::shared_ptr processor, boost::shared_ptr< { Glib::Threads::RWLock::WriterLock lm (_processor_lock); ProcessorState pstate (this); + Glib::Threads::Mutex::Lock lx (AudioEngine::instance()->process_lock ()); boost::shared_ptr pi; boost::shared_ptr porti; @@ -986,8 +987,6 @@ Route::add_processor (boost::shared_ptr processor, boost::shared_ptr< // configure redirect ports properly, etc. { - Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ()); - if (configure_processors_unlocked (err)) { pstate.restore (); configure_processors_unlocked (0); // it worked before we tried to add it ... @@ -1117,6 +1116,7 @@ Route::add_processors (const ProcessorList& others, boost::shared_ptr { Glib::Threads::RWLock::WriterLock lm (_processor_lock); ProcessorState pstate (this); + Glib::Threads::Mutex::Lock lx (AudioEngine::instance()->process_lock ()); for (ProcessorList::const_iterator i = others.begin(); i != others.end(); ++i) { @@ -1137,8 +1137,8 @@ Route::add_processors (const ProcessorList& others, boost::shared_ptr (*i)->activate (); } + /* Think: does this really need to be called for every processor in the loop? */ { - Glib::Threads::Mutex::Lock lm (AudioEngine::instance()->process_lock ()); if (configure_processors_unlocked (err)) { pstate.restore (); configure_processors_unlocked (0); // it worked before we tried to add it ...