Comment 1 for bug 1664180

== Stacktrace =================================
#0 0x00007effb88ff0b9 in mir::graphics::mesa::RealKMSOutput::max_refresh_rate (this=0x55c4b506e220) at /home/nick/Work/ubuntu/mir/mir-0.26.0+17.04.20170126.3/src/platforms/mesa/server/kms/real_kms_output.cpp:102
        current_mode = <error reading variable>
#1 0x00007effb88de663 in mir::graphics::mesa::DisplayBuffer::post (this=0x55c4b51d0200) at /home/nick/Work/ubuntu/mir/mir-0.26.0+17.04.20170126.3/src/platforms/mesa/server/kms/display_buffer.cpp:355
        output = std::shared_ptr (count 2, weak 0) 0x55c4b506e220
        min_frame_interval = {__r = 139636366146016}
        bufobj = 0x7effa00080e0
        predicted_render_time = {__r = 5}
#2 0x00007effbec63fce in mir::compositor::CompositingFunctor::operator() (this=0x55c4b51f9c30) at /home/nick/Work/ubuntu/mir/mir-0.26.0+17.04.20170126.3/src/server/compositor/multi_threaded_compositor.cpp:143
        delay = {__r = 139636366355200}
        pending = -1095108196
        lock = {_M_device = 0x55c4b51f9c68, _M_owns = false}
        disp_listener = std::shared_ptr (count 6, weak 2) 0x55c4b511b878
        display_registration = {deleter = {__this = 0x55c4b51f9c30, __disp_listener = std::shared_ptr (count 6, weak 2) 0x55c4b511b878}, owner = true}
        compositor_registration = {deleter = {__this = 0x55c4b51f9c30, __compositors = std::vector of length 1, capacity 1 = {std::tuple containing = {[1] = 0x55c4b51d0200, [2] = std::unique_ptr<mir::compositor::DisplayBufferCompositor> containing 0x7effa0009010}}}, owner = true}
        compositors = std::vector of length 1, capacity 1 = {std::tuple containing = {[1] = 0x55c4b51d0200, [2] = std::unique_ptr<mir::compositor::DisplayBufferCompositor> containing 0x7effa0009010}}
#3 0x00007effbec677ae in std::_Function_handler<void (), std::reference_wrapper<mir::compositor::CompositingFunctor> >::_M_invoke(std::_Any_data const&) (__functor=...) at /usr/include/c++/6/functional:1761
No locals.
#4 0x00007effbeb0cf96 in std::function<void ()>::operator()() const (this=0x7effaf7fdd80) at /usr/include/c++/6/functional:2127
No locals.
#5 0x00007effbedb75ef in (anonymous namespace)::Task::execute (this=0x7effaf7fdd80) at /home/nick/Work/ubuntu/mir/mir-0.26.0+17.04.20170126.3/src/server/thread/basic_thread_pool.cpp:40
No locals.
#6 0x00007effbedb7958 in (anonymous namespace)::Worker::operator() (this=0x55c4b528cde0) at /home/nick/Work/ubuntu/mir/mir-0.26.0+17.04.20170126.3/src/server/thread/basic_thread_pool.cpp:91
        task = {task = {<std::_Maybe_unary_or_binary_function<void>> = {<No data fields>}, <std::_Function_base> = {static _M_max_size = 16, static _M_max_align = 8, _M_functor = {_M_unused = {_M_object = 0x55c4b51f9c30, _M_const_object = 0x55c4b51f9c30, _M_function_pointer = 0x55c4b51f9c30, _M_member_pointer = (void (std::_Undefined_class::*)(std::_Undefined_class * const)) 0x55c4b51f9c30}, _M_pod_data = "0\234\037\265\304U\000\000\000\000\000\000\000\000\000"}, _M_manager = 0x7effbec677b1 <std::_Function_base::_Ref_manager<mir::compositor::CompositingFunctor>::_M_manager(std::_Any_data&, std::_Any_data const&, std::_Manager_operation)>}, _M_invoker = 0x7effbec67783 <std::_Function_handler<void (), std::reference_wrapper<mir::compositor::CompositingFunctor> >::_M_invoke(std::_Any_data const&)>}, promise = {_M_future = std::shared_ptr (count 2, weak 0) 0x55c4b52ed0f0, _M_storage = std::unique_ptr<std::__future_base::_Result<void>> containing 0x55c4b5256d30}, task_exception = {_M_exception_object = 0x0}}
        lock = {_M_device = 0x55c4b528ce38, _M_owns = false}
#7 0x00007effbedba80a in std::__invoke_impl<void, (anonymous namespace)::Worker&> (__f=...) at /usr/include/c++/6/functional:210
No locals.
#8 0x00007effbedba7cc in std::__invoke<(anonymous namespace)::Worker&> (__fn=...) at /usr/include/c++/6/functional:251
No locals.
#9 0x00007effbedba776 in std::reference_wrapper<(anonymous namespace)::Worker>::operator()<>(void) const (this=0x55c4b5074758) at /usr/include/c++/6/functional:465
No locals.
#10 0x00007effbedba754 in std::_Bind_simple<std::reference_wrapper<(anonymous namespace)::Worker>()>::_M_invoke<>(std::_Index_tuple<>) (this=0x55c4b5074758) at /usr/include/c++/6/functional:1391
No locals.
#11 0x00007effbedba6de in std::_Bind_simple<std::reference_wrapper<(anonymous namespace)::Worker>()>::operator()(void) (this=0x55c4b5074758) at /usr/include/c++/6/functional:1380
No locals.
#12 0x00007effbedba6ae in std::thread::_State_impl<std::_Bind_simple<std::reference_wrapper<(anonymous namespace)::Worker>()> >::_M_run(void) (this=0x55c4b5074750) at /usr/include/c++/6/thread:196
No locals.
#13 0x00007effc089fb2f in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
No symbol table info available.
#14 0x00007effc03b66ca in start_thread (arg=0x7effaf7fe700) at pthread_create.c:333
        __res = <optimised out>
        pd = 0x7effaf7fe700
        now = <optimised out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {139636626155264, -6004600387093277814, 0, 140732472064719, 139636626155968, 139636626155264, 5860310377750975370, 5860554980112192394}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimised out>
        pagesize_m1 = <optimised out>
        sp = <optimised out>
        freesize = <optimised out>
        __PRETTY_FUNCTION__ = "start_thread"
#15 0x00007effc00f00ff in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105
No locals.