Different test (NestedServer.display_configuration_changes_are_forwarded_to_host) but probably the same cause here:

https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial+overlay/1563/consoleFull

13:37:35 11: [ RUN ] NestedServer.display_configuration_changes_are_forwarded_to_host
13:37:35 11: [2016-07-19 13:37:35.706741] mirserver: Starting
13:37:35 11: [2016-07-19 13:37:35.708231] mirserver: Selected driver: mir:stub-graphics (version 0.25.0)
13:37:35 11: [2016-07-19 13:37:35.710741] mirserver: Using software cursor
13:37:35 11: [2016-07-19 13:37:35.725705] mirserver: Selected input driver: mir:stub-input (version: 0.25.0)
13:37:35 11: [2016-07-19 13:37:35.726332] mirserver: Mir version 0.25.0
13:37:35 11: [2016-07-19 13:37:35.743620] mirserver: Starting
13:37:35 11: [2016-07-19 13:37:35.785883] mirserver: Using nested cursor
13:37:35 11: [2016-07-19 13:37:35.808687] mirserver: Initial display configuration:
13:37:35 11: [2016-07-19 13:37:35.809652] mirserver: 1.1: VGA 0.0" 0x0mm
13:37:35 11: [2016-07-19 13:37:35.809838] mirserver: Current mode 640x480 60.00Hz
13:37:35 11: [2016-07-19 13:37:35.810001] mirserver: Preferred mode 640x480 60.00Hz
13:37:35 11: [2016-07-19 13:37:35.810143] mirserver: Logical position +0+0
13:37:35 11: [2016-07-19 13:37:35.810529] mirserver: 1.2: VGA 0.0" 0x0mm
13:37:35 11: [2016-07-19 13:37:35.810693] mirserver: Current mode 1920x1080 60.00Hz
13:37:35 11: [2016-07-19 13:37:35.810850] mirserver: Preferred mode 1920x1080 60.00Hz
13:37:35 11: [2016-07-19 13:37:35.810987] mirserver: Logical position +640+0
13:37:36 11: [2016-07-19 13:37:35.814391] mirserver: Mir version 0.25.0
13:37:36 11: [2016-07-19 13:37:35.898938] mirserver: New display configuration:
13:37:36 11: [2016-07-19 13:37:35.899509] mirserver: 1.1: VGA 0.0" 0x0mm
13:37:36 11: [2016-07-19 13:37:35.899688] mirserver: Disabled
13:37:36 11: [2016-07-19 13:37:35.900068] mirserver: 1.2: VGA 0.0" 0x0mm
13:37:36 11: [2016-07-19 13:37:35.900237] mirserver: Current mode 1920x1080 60.00Hz
13:37:36 11: [2016-07-19 13:37:35.900396] mirserver: Preferred mode 1920x1080 60.00Hz
13:37:36 11: [2016-07-19 13:37:35.900535] mirserver: Logical position +640+0
13:37:36 11: ==29217== Thread 11 Input dispatch:
13:37:36 11: ==29217== Invalid read of size 8
13:37:36 11: ==29217== at 0x410E6E0: mir::graphics::nested::detail::DisplayBuffer::event_thunk(MirSurface*, MirEvent const*, void*) (display_buffer.cpp:109)
13:37:36 11: ==29217== by 0x4E73CED: std::_Function_handler<void (MirEvent*), std::function<void (MirEvent const*)> >::_M_invoke(std::_Any_data const&, MirEvent*&&) (functional:2267)
13:37:36 11: ==29217== by 0x4EA037F: mir::input::receiver::android::InputReceiver::process_and_maybe_send_event() [clone .constprop.51] (functional:2267)
13:37:36 11: ==29217== by 0x41F9259: operator() (functional:2267)
13:37:36 11: ==29217== by 0x41F9259: (anonymous namespace)::DispatchableAdaptor::dispatch(unsigned int) [clone .lto_priv.444] (multiplexing_dispatchable.cpp:57)
13:37:36 11: ==29217== by 0x41FA35C: mir::dispatch::MultiplexingDispatchable::dispatch(unsigned int) (multiplexing_dispatchable.cpp:210)
13:37:36 11: ==29217== by 0x41FA35C: mir::dispatch::MultiplexingDispatchable::dispatch(unsigned int) (multiplexing_dispatchable.cpp:210)
13:37:36 11: ==29217== by 0x42096DE: (anonymous namespace)::dispatch_loop(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::shared_ptr<mir::dispatch::ThreadedDispatcher::ThreadShutdownRequestHandler>, std::shared_ptr<mir::dispatch::Dispatchable>, std::function<void ()> const&) [clone .lto_priv.313] (threaded_dispatcher.cpp:211)
13:37:36 11: ==29217== by 0x4202CED: _M_invoke (functional:1531)
13:37:36 11: ==29217== by 0x4202CED: operator() (functional:1520)
13:37:36 11: ==29217== by 0x4202CED: std::thread::_Impl<std::_Bind_simple<void (*(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::shared_ptr<mir::dispatch::ThreadedDispatcher::ThreadShutdownRequestHandler>, std::shared_ptr<mir::dispatch::MultiplexingDispatchable>, std::function<void ()>))(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::shared_ptr<mir::dispatch::ThreadedDispatcher::ThreadShutdownRequestHandler>, std::shared_ptr<mir::dispatch::Dispatchable>, std::function<void ()> const&)> >::_M_run() (thread:115)
13:37:36 11: ==29217== by 0x5838C7F: ??? (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21)
13:37:36 11: ==29217== by 0x5D206F9: start_thread (pthread_create.c:333)
13:37:36 11: ==29217== by 0x603CB5C: clone (clone.S:109)
13:37:36 11: ==29217== Address 0xbde40b0 is 64 bytes inside a block of size 136 free'd
13:37:36 11: ==29217== at 0x4C2F24B: operator delete(void*) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
13:37:36 11: ==29217== by 0x40F0178: std::__detail::_Hashtable_alloc<std::allocator<std::__detail::_Hash_node<std::pair<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> const, std::shared_ptr<mir::frontend::ClientBufferTracker> >, true> > >::_M_deallocate_node(std::__detail::_Hash_node<std::pair<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> const, std::shared_ptr<mir::frontend::ClientBufferTracker> >, true>*) [clone .isra.50] [clone .lto_priv.2032] (shared_ptr_base.h:150)
13:37:36 11: ==29217== by 0x4111AC7: std::_Hashtable<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int>, std::pair<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> const, std::shared_ptr<mir::frontend::ClientBufferTracker> >, std::allocator<std::pair<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> const, std::shared_ptr<mir::frontend::ClientBufferTracker> > >, std::__detail::_Select1st, std::equal_to<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> >, std::hash<mir::IntWrapper<mir::frontend::detail::SessionsBufferStreamIdTag, int> >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> >::~_Hashtable() (hashtable_policy.h:1986)
13:37:36 11: ==29217== by 0x412FDC8: mir::graphics::nested::Display::create_surfaces(mir::graphics::DisplayConfiguration const&) [clone .constprop.835] (unordered_map.h:98)
13:37:36 11: ==29217== by 0x4132F5A: mir::graphics::nested::Display::configure(mir::graphics::DisplayConfiguration const&) (display.cpp:240)
13:37:36 11: ==29217== by 0x40C46AA: mir::scene::MediatingDisplayChanger::apply_config(std::shared_ptr<mir::graphics::DisplayConfiguration> const&, mir::DisplayChanger::SystemStateHandling) (mediating_display_changer.cpp:267)
13:37:36 11: ==29217== by 0x40C5194: std::_Function_handler<void (), mir::scene::MediatingDisplayChanger::MediatingDisplayChanger(std::shared_ptr<mir::graphics::Display> const&, std::shared_ptr<mir::compositor::Compositor> const&, std::shared_ptr<mir::graphics::DisplayConfigurationPolicy> const&, std::shared_ptr<mir::scene::SessionContainer> const&, std::shared_ptr<mir::scene::SessionEventHandlerRegister> const&, std::shared_ptr<mir::ServerActionQueue> const&, std::shared_ptr<mir::graphics::DisplayConfigurationReport> const&, std::shared_ptr<mir::input::InputRegion> const&, std::shared_ptr<mir::time::AlarmFactory> const&)::{lambda(std::shared_ptr<mir::scene::Session> const&)#1}::operator()(std::shared_ptr<mir::scene::Session> const&) const::{lambda()#1}>::_M_invoke(std::_Any_data const&) (mediating_display_changer.cpp:310)
13:37:36 11: ==29217== by 0x40844E6: operator() (functional:2267)
13:37:36 11: ==29217== by 0x40844E6: operator() (glib_main_loop.cpp:237)
13:37:36 11: ==29217== by 0x40844E6: std::_Function_handler<void (), mir::GLibMainLoop::enqueue(void const*, std::function<void ()> const&)::{lambda()#1}>::_M_invoke(std::_Any_data const&) (functional:1871)
13:37:36 11: ==29217== by 0x4083AD7: mir::detail::add_server_action_gsource(_GMainContext*, void const*, std::function<void ()> const&, std::function<bool (void const*)> const&)::ServerActionGSource::dispatch(_GSource*, int (*)(void*), void*) (functional:2267)
13:37:36 11: ==29217== by 0x6A1E1A6: g_main_context_dispatch (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.1)
13:37:36 11: ==29217== by 0x6A1E3FF: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.1)
13:37:36 11: ==29217== by 0x6A1E4AB: g_main_context_iteration (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.4800.1)
13:37:36 11: ==29217== by 0x4084A50: mir::GLibMainLoop::run() (glib_main_loop.cpp:145)
13:37:36 11: ==29217== by 0x408A4B0: mir::run_mir(mir::ServerConfiguration&, std::function<void (mir::DisplayServer&)>, std::function<void (int)> const&) (display_server.cpp:217)
13:37:36 11: ==29217== by 0x4096625: mir::Server::run() (server.cpp:453)
13:37:36 11: ==29217== by 0x793E23: operator() (async_server_runner.cpp:88)
13:37:36 11: ==29217== by 0x793E23: _M_invoke<> (functional:1531)
13:37:36 11: ==29217== by 0x793E23: operator() (functional:1520)
13:37:36 11: ==29217== by 0x793E23: std::thread::_Impl<std::_Bind_simple<mir_test_framework::AsyncServerRunner::start_server()::{lambda()#2} ()> >::_M_run() (thread:115)
13:37:36 11: ==29217== by 0x5838C7F: ??? (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21)
13:37:36 11: ==29217== by 0x5D206F9: start_thread (pthread_create.c:333)
13:37:36 11: ==29217== by 0x603CB5C: clone (clone.S:109)
13:37:36 11: ==29217== Block was alloc'd at
13:37:36 11: ==29217== at 0x4C2E0EF: operator new(unsigned long) (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
13:37:36 11: ==29217== by 0x4134838: mir::graphics::nested::Display::create_surfaces(mir::graphics::DisplayConfiguration const&)::{lambda(mir::graphics::OverlappingOutputGroup const&)#1}::operator()(mir::graphics::OverlappingOutputGroup const&) const [clone .lto_priv.2105] (new_allocator.h:104)
13:37:36 11: ==29217== by 0x41D8993: operator() (functional:2267)
13:37:36 11: ==29217== by 0x41D8993: mir::graphics::OverlappingOutputGrouping::for_each_group(std::function<void (mir::graphics::OverlappingOutputGroup const&)> const&) (overlapping_output_grouping.cpp:92)
13:37:36 11: ==29217== by 0x412FBF5: mir::graphics::nested::Display::create_surfaces(mir::graphics::DisplayConfiguration const&) [clone .constprop.835] (display.cpp:322)
13:37:36 11: ==29217== by 0x40E4E25: std::_Function_handler<std::shared_ptr<mir::graphics::Display> (), mir::DefaultServerConfiguration::the_display()::{lambda()#1}>::_M_invoke(std::_Any_data const&) (display.cpp:201)
13:37:36 11: ==29217== by 0x411AB22: mir::CachedPtr<mir::MainLoop>::operator()(std::function<std::shared_ptr<mir::MainLoop> ()>) (functional:2267)
13:37:36 11: ==29217== by 0x40E5686: mir::DefaultServerConfiguration::the_display() (default_configuration.cpp:166)
13:37:37 11: ==29217== by 0x408A231: mir::run_mir(mir::ServerConfiguration&, std::function<void (mir::DisplayServer&)>, std::function<void (int)> const&) (display_server.cpp:58)
13:37:37 11: ==29217== by 0x4096625: mir::Server::run() (server.cpp:453)
13:37:37 11: ==29217== by 0x793E23: operator() (async_server_runner.cpp:88)
13:37:37 11: ==29217== by 0x793E23: _M_invoke<> (functional:1531)
13:37:37 11: ==29217== by 0x793E23: operator() (functional:1520)
13:37:37 11: ==29217== by 0x793E23: std::thread::_Impl<std::_Bind_simple<mir_test_framework::AsyncServerRunner::start_server()::{lambda()#2} ()> >::_M_run() (thread:115)
13:37:37 11: ==29217== by 0x5838C7F: ??? (in /usr/lib/x86_64-linux-gnu/libstdc++.so.6.0.21)
13:37:37 11: ==29217== by 0x5D206F9: start_thread (pthread_create.c:333)
13:37:37 11: ==29217== by 0x603CB5C: clone (clone.S:109)
13:37:37 11: ==29217==
13:37:37 11: [2016-07-19 13:37:35.970331] mirserver: New display configuration:
13:37:37 11: [2016-07-19 13:37:35.970916] mirserver: 1.1: VGA 0.0" 0x0mm
13:37:37 11: [2016-07-19 13:37:35.971100] mirserver: Current mode 640x480 60.00Hz
13:37:37 11: [2016-07-19 13:37:35.971263] mirserver: Preferred mode 640x480 60.00Hz
13:37:37 11: [2016-07-19 13:37:35.971402] mirserver: Logical position +0+0
13:37:37 11: [2016-07-19 13:37:35.972002] mirserver: 1.2: VGA 0.0" 0x0mm
13:37:37 11: [2016-07-19 13:37:35.972263] mirserver: Current mode 1920x1080 60.00Hz
13:37:37 11: [2016-07-19 13:37:35.972512] mirserver: Preferred mode 1920x1080 60.00Hz
13:37:37 11: [2016-07-19 13:37:35.976867] mirserver: Logical position +640+0
13:37:37 11: [2016-07-19 13:37:35.980882] mirserver: Stopping
13:37:37 11: [2016-07-19 13:37:36.280002] mirserver: Stopping
13:37:37 11: [ OK ] NestedServer.display_configuration_changes_are_forwarded_to_host (668 ms)