MotionMark: subtract with overflow

[jonathandturner]

Looks like we can't get through MotionMark anymore. Unclear yet when it regressed. This backtrace happens just after the first test in the suite.

cc @glennw

Backtrace:

attempt to subtract with overflow (thread main, at /Users/jturner/Source/servo/.cargo/git/checkouts/webrender-c3596abe1cf4f320/d126eba/webrender/src/device.rs:1738)
stack backtrace:
   0:        0x10f1ad3c4 - backtrace::backtrace::trace::hc04eef90157d46bd
   1:        0x10f1ae6bf - backtrace::capture::Backtrace::new::h5e598cddffa26117
   2:        0x10da39686 - servo::main::_$u7b$$u7b$closure$u7d$$u7d$::hd0aafd4d730bcb99
   3:        0x113815666 - std::panicking::rust_panic_with_hook::h2bd2f0b446f0face
                        at src/libstd/panicking.rs:550
   4:        0x1138154c4 - std::panicking::begin_panic<collections::string::String>
                        at src/libstd/panicking.rs:511
   5:        0x113815432 - std::panicking::begin_panic_fmt::h2948dd4668f99175
                        at src/libstd/panicking.rs:495
   6:        0x113815397 - rust_begin_unwind
                        at src/libstd/panicking.rs:471
   7:        0x11383d5f0 - core::panicking::panic_fmt::hb2e726f3b579b19d
                        at src/libcore/panicking.rs:69
   8:        0x11383d4f4 - core::panicking::panic::hafbe89720e5223c3
                        at src/libcore/panicking.rs:49
   9:        0x1121a5208 - webrender::device::Device::update_texture::h8152f1448061ec14
  10:        0x112241271 - webrender::renderer::Renderer::update_texture_cache::hd610b7d7943d9b6c
  11:        0x11220c160 - webrender::renderer::Renderer::render::_$u7b$$u7b$closure$u7d$$u7d$::he5d9d628762261da
  12:        0x11220b3c5 - webrender::profiler::TimeProfileCounter::profile::h75b84045babc7abe
  13:        0x11223ff6b - webrender::renderer::Renderer::render::h774b8d7d420477a3
  14:        0x10da18d7d - _$LT$compositing..compositor..IOCompositor$LT$Window$GT$$GT$::composite_specific_target::_$u7b$$u7b$closure$u7d$$u7d$::h09f144d1ac7f7d45
  15:        0x10da17cd2 - profile_traits::time::profile::h70cf22a7c8b4b2fa
  16:        0x10d9c8c4e - _$LT$compositing..compositor..IOCompositor$LT$Window$GT$$GT$::composite_specific_target::hdd34a6574e85e689
  17:        0x10d9ceb6f - _$LT$compositing..compositor..IOCompositor$LT$Window$GT$$GT$::composite::h58a0de7672154ec8
  18:        0x10d9bfff1 - _$LT$compositing..compositor..IOCompositor$LT$Window$GT$$GT$::handle_events::hc1405c3a8ce94d54
  19:        0x10da3a0ca - _$LT$servo..Browser$LT$Window$GT$$GT$::handle_events::ha33c1c9cb4e76fe7
  20:        0x10da38d7a - servo::main::h36b85a98efbb451b
  21:        0x1138167ca - __rust_maybe_catch_panic
                        at src/libpanic_unwind/lib.rs:98
  22:        0x113815a91 - std::rt::lang_start::hbda94898b2b88ae4
                        at src/libstd/rt.rs:57
  23:        0x10da39c19 - main
ERROR:servo: attempt to subtract with overflow
Servo exited with return value 101

Part of #13373.

[jonathandturner]

Pinging @glennw - any thoughts on this one?

[glennw]

@jonathandturner Not off the top of my head - will need to debug it carefully.

[jonathandturner]

I don't see the crash on this 2012 Macbook Air (the original post was on a 2015 MBP). Instead, I'm seeing this:

ERROR:script::dom::bindings::error: Error at http://browserbench.org/MotionMark/resources/extensions.js:112:13 prefix is undefined

Unclear whether the crash is video card related.

[DavidLarsson]

I'm new to the project (and to Rust), so I thought I'd start softly with reproducing this bug. It crashes on my Dell XPS:

CPU: Intel® Core™ i7-7500U CPU @ 2.70GHz × 4
Graphics: Intel® Kabylake GT2

with Ubuntu 16.04 and the following kernel configuration:

Linux 4.4.0-81-generic #104-Ubuntu SMP Wed Jun 14 08:17:06 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

Repeated twice with the same origin in thread RenderBackend texture_cache.rs:820, dissimilar from @jonathandturner . But similarly, the crash happens right after the first test finishes.

My backtrace seems to be much longer and involving at least two threads:

attempt to subtract with overflow (thread RenderBackend, at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/texture_cache.rs:820)
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d97be956a4 - core::panicking::panic
                        at /checkout/src/libcore/panicking.rs:51
   9:     0x55d9773e463a - webrender::texture_cache::{{impl}}::insert
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/texture_cache.rs:820
  10:     0x55d9773dd05a - webrender::resource_cache::{{impl}}::update_texture_cache
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/resource_cache.rs:721
  11:     0x55d9773dd2cb - webrender::resource_cache::{{impl}}::finalize_image_request
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/resource_cache.rs:758
  12:     0x55d9773db7c7 - webrender::resource_cache::{{impl}}::block_until_all_resources_added
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/resource_cache.rs:605
  13:     0x55d9773c5d9e - webrender::frame_builder::{{impl}}::build
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/frame_builder.rs:1413
  14:     0x55d9773b754e - webrender::frame::{{impl}}::build_frame::{{closure}}
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/frame.rs:1173
  15:     0x55d9772cc8cc - core::option::{{impl}}::map<&mut webrender::frame_builder::FrameBuilder,webrender::tiling::Frame,closure>
                        at /checkout/src/libcore/option.rs:398
  16:     0x55d9773b7262 - webrender::frame::{{impl}}::build_frame
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/frame.rs:1172
  17:     0x55d9773b6f92 - webrender::frame::{{impl}}::build
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/frame.rs:1150
  18:     0x55d977094aaf - webrender::render_backend::{{impl}}::render
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/render_backend.rs:514
  19:     0x55d977094647 - webrender::render_backend::{{impl}}::run::{{closure}}
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/render_backend.rs:434
  20:     0x55d97708a2ba - webrender::profiler::{{impl}}::profile<webrender::internal_types::RendererFrame,closure>
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/profiler.rs:154
  21:     0x55d977092756 - webrender::render_backend::{{impl}}::run
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/render_backend.rs:433
  22:     0x55d9770b7f23 - webrender::renderer::{{impl}}::new::{{closure}}
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender/src/renderer.rs:1158
  23:     0x55d976fa0dfa - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  24:     0x55d976fa46b3 - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  25:     0x55d976f708ba - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  26:     0x55d9772d4429 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  27:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  28:     0x55d9772d2f9c - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  29:     0x55d976fa3505 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  30:     0x55d976fa44ae - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  31:     0x55d976fe64d3 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  32:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  33:     0x7fc9ef1e16b9 - start_thread
  34:     0x7fc9eed013dc - clone
  35:                0x0 - <unknown>
ERROR:servo: attempt to subtract with overflow
called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 104, message: "Connection reset by peer" } }) (thread CanvasThread, at /checkout/src/libcore/result.rs:860)
called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } }) (thread LayoutThread PipelineId { namespace_id: PipelineNamespaceId(0), index: PipelineIndex(0) }, at /checkout/src/libcore/result.rs:860)
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d97b7dcbbc - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
   9:     0x55d97b7944c7 - core::result::{{impl}}::unwrap<(),alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  10:     0x55d97b7a32f1 - webrender_api::api::{{impl}}::update_image
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender_api/src/api.rs:260
  11:     0x55d9774fa037 - canvas::canvas_paint_thread::{{impl}}::send_data::{{closure}}
                        at components/canvas/canvas_paint_thread.rs:577
  12:     0x55d97749d177 - azure::azure_hl::{{impl}}::with_data<closure>
                        at .cargo/git/checkouts/rust-azure-984e17605d95e219/71de5aa/src/azure_hl.rs:1064
  13:     0x55d9774f9d95 - canvas::canvas_paint_thread::{{impl}}::send_data
                        at components/canvas/canvas_paint_thread.rs:562
  14:     0x55d9774314f9 - canvas::canvas_paint_thread::{{impl}}::start::{{closure}}
                        at components/canvas/canvas_paint_thread.rs:207
  15:     0x55d977419702 - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  16:     0x55d977478a0a - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  17:     0x55d9774336e2 - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  18:     0x55d9773f96c2 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  19:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  20:     0x55d9773f9225 - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  21:     0x55d977477439 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  22:     0x55d977478831 - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  23:     0x55d977498c07 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  24:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  25:     0x7fc9ef1e16b9 - start_thread
  26:     0x7fc9eed013dc - clone
  27:                0x0 - <unknown>
ERROR:servo: called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 104, message: "Connection reset by peer" } })
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d97b7dcbbc - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
   9:     0x55d97b7944c7 - core::result::{{impl}}::unwrap<(),alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  10:     0x55d97b7a4885 - webrender_api::api::{{impl}}::generate_frame
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender_api/src/api.rs:411
  11:     0x55d9763b92c0 - layout_thread::{{impl}}::compute_abs_pos_and_build_display_list::{{closure}}
                        at components/layout_thread/lib.rs:1021
  12:     0x55d976281444 - profile_traits::time::profile<(),closure>
                        at components/profile_traits/time.rs:121
  13:     0x55d9761eaa1f - layout_thread::{{impl}}::compute_abs_pos_and_build_display_list
                        at components/layout_thread/lib.rs:924
  14:     0x55d9761f2eed - layout_thread::{{impl}}::perform_post_main_layout_passes
                        at components/layout_thread/lib.rs:1601
  15:     0x55d9761f2a83 - layout_thread::{{impl}}::perform_post_style_recalc_layout_passes
                        at components/layout_thread/lib.rs:1586
  16:     0x55d9761f1ec8 - layout_thread::{{impl}}::tick_animations
                        at components/layout_thread/lib.rs:1489
  17:     0x55d9761f18c0 - layout_thread::{{impl}}::tick_all_animations
                        at components/layout_thread/lib.rs:1450
  18:     0x55d9761e6dc5 - layout_thread::{{impl}}::handle_request_helper
                        at components/layout_thread/lib.rs:672
  19:     0x55d9761e63b1 - layout_thread::{{impl}}::handle_request
                        at components/layout_thread/lib.rs:626
  20:     0x55d9761e5709 - layout_thread::{{impl}}::start
                        at components/layout_thread/lib.rs:557
  21:     0x55d9761e2f13 - layout_thread::{{impl}}::create::{{closure}}::{{closure}}
                        at components/layout_thread/lib.rs:290
  22:     0x55d97611979c - profile_traits::mem::{{impl}}::run_with_memory_reporting<closure,fn(profile_traits::mem::ReportsChan) -> script_layout_interface::message::Msg,script_layout_interface::message::Msg,std::sync::mpsc::Sender<script_layout_interface::message::Msg>>
                        at components/profile_traits/mem.rs:63
  23:     0x55d9763b72d4 - layout_thread::{{impl}}::create::{{closure}}
                        at components/layout_thread/lib.rs:289
  24:     0x55d9762a8ada - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  25:     0x55d976144053 - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  26:     0x55d9760d958a - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  27:     0x55d976144ef9 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  28:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  29:     0x55d97614482c - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  30:     0x55d976143c75 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  31:     0x55d9762a9f3e - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  32:     0x55d9763096b3 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  33:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  34:     0x7fc9ef1e16b9 - start_thread
  35:     0x7fc9eed013dc - clone
  36:                0x0 - <unknown>
ERROR:servo: called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } })
called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 104, message: "Connection reset by peer" } }) (thread LayoutThread PipelineId { namespace_id: PipelineNamespaceId(1), index: PipelineIndex(3) }, at /checkout/src/libcore/result.rs:860)
called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } }) (thread CanvasThread, at /checkout/src/libcore/result.rs:860)
called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } }) (thread Constellation, at /checkout/src/libcore/result.rs:860)
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d97b7dcbbc - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
   9:     0x55d97b7944c7 - core::result::{{impl}}::unwrap<(),alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  10:     0x55d97b7a33fe - webrender_api::api::{{impl}}::delete_image
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender_api/src/api.rs:266
  11:     0x55d9774fc651 - canvas::canvas_paint_thread::{{impl}}::drop
                        at components/canvas/canvas_paint_thread.rs:749
  12:     0x55d977421a84 - core::ptr::drop_in_place<canvas::canvas_paint_thread::CanvasPaintThread>
                        at /checkout/src/libcore/ptr.rs:60
  13:     0x55d977431248 - canvas::canvas_paint_thread::{{impl}}::start::{{closure}}
                        at components/canvas/canvas_paint_thread.rs:215
  14:     0x55d977419702 - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  15:     0x55d977478a0a - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  16:     0x55d9774336e2 - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  17:     0x55d9773f96c2 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  18:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  19:     0x55d9773f9225 - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  20:     0x55d977477439 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  21:     0x55d977478831 - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  22:     0x55d977498c07 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  23:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  24:     0x7fc9ef1e16b9 - start_thread
  25:     0x7fc9eed013dc - clone
  26:                0x0 - <unknown>
stack backtrace:
ERROR:servo: called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } })
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d97b7dcbbc - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
   9:     0x55d97b7944c7 - core::result::{{impl}}::unwrap<(),alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  10:     0x55d97b7a28d4 - webrender_api::api::{{impl}}::create_api
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender_api/src/api.rs:179
  11:     0x55d975c57f6d - constellation::pipeline::{{impl}}::start_all<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/pipeline.rs:477
  12:     0x55d975c5a2ca - constellation::pipeline::{{impl}}::spawn<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/pipeline.rs:278
  13:     0x55d975cee644 - constellation::constellation::{{impl}}::new_pipeline<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:665
  14:     0x55d975cecbd1 - constellation::constellation::{{impl}}::handle_panic<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:1420
  15:     0x55d975cf69f0 - constellation::constellation::{{impl}}::handle_log_entry<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:1439
  16:     0x55d975d160f1 - constellation::constellation::{{impl}}::handle_request_from_compositor<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:971
  17:     0x55d975cf18bc - constellation::constellation::{{impl}}::handle_request<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:859
  18:     0x55d975d1caaa - constellation::constellation::{{impl}}::run<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:589
  19:     0x55d975ba9c48 - constellation::constellation::{{impl}}::start::{{closure}}<script_layout_interface::message::Msg,layout_thread::LayoutThread,script::script_thread::ScriptThread>
                        at components/constellation/constellation.rs:577
  20:     0x55d975b41b1a - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  21:     0x55d975b4f453 - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  22:     0x55d975b2a07a - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  23:     0x55d975d4d2b9 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  24:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  25:     0x55d975d4d0ec - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
thread panicked while panicking. aborting.
  26:     0x55d975b4e8c5 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  27:     0x55d975b4f24e - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  28:     0x55d975b74de3 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  29:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  30:     0x7fc9ef1e16b9 - start_thread
  31:     0x7fc9eed013dc - clone
  32:                0x0 - <unknown>
ERROR:servo: called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 32, message: "Broken pipe" } })
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759db493 - servo::main::{{closure}}
                        at ports/servo/main.rs:129
   3:     0x55d97be66b19 - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:550
   4:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   5:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   6:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   7:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   8:     0x55d976707d3c - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
   9:     0x55d97649857f - core::result::{{impl}}::unwrap<canvas_traits::CanvasData,alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  10:     0x55d976510c16 - layout::display_list_builder::{{impl}}::build_fragment_type_specific_display_items
                        at components/layout/display_list_builder.rs:1955
  11:     0x55d97650ff0a - layout::display_list_builder::{{impl}}::build_display_list
                        at components/layout/display_list_builder.rs:1835
  12:     0x55d9765df028 - layout::display_list_builder::{{impl}}::build_display_list_for_inline_fragment_at_index
                        at components/layout/display_list_builder.rs:2740
  13:     0x55d9765df448 - layout::display_list_builder::{{impl}}::build_display_list_for_inline
                        at components/layout/display_list_builder.rs:2773
  14:     0x55d9765f42ec - layout::inline::{{impl}}::build_display_list
                        at components/layout/inline.rs:1676
  15:     0x55d976608b7f - layout::traversal::{{impl}}::traverse
                        at components/layout/traversal.rs:236
  16:     0x55d976608d74 - layout::traversal::{{impl}}::traverse
                        at components/layout/traversal.rs:241
  17:     0x55d976608d74 - layout::traversal::{{impl}}::traverse
                        at components/layout/traversal.rs:241
  18:     0x55d9765fa5d4 - layout::sequential::build_display_list_for_subtree
                        at components/layout/sequential.rs:96
  19:     0x55d9763b83bb - layout_thread::{{impl}}::compute_abs_pos_and_build_display_list::{{closure}}
                        at components/layout_thread/lib.rs:947
  20:     0x55d976281444 - profile_traits::time::profile<(),closure>
                        at components/profile_traits/time.rs:121
  21:     0x55d9761eaa1f - layout_thread::{{impl}}::compute_abs_pos_and_build_display_list
                        at components/layout_thread/lib.rs:924
  22:     0x55d9761f2eed - layout_thread::{{impl}}::perform_post_main_layout_passes
                        at components/layout_thread/lib.rs:1601
  23:     0x55d9761f2a83 - layout_thread::{{impl}}::perform_post_style_recalc_layout_passes
                        at components/layout_thread/lib.rs:1586
  24:     0x55d9761ee0ad - layout_thread::{{impl}}::handle_reflow
                        at components/layout_thread/lib.rs:1301
  25:     0x55d9763b7bfd - layout_thread::{{impl}}::handle_request_helper::{{closure}}
                        at components/layout_thread/lib.rs:670
  26:     0x55d976282296 - profile_traits::time::profile<(),closure>
                        at components/profile_traits/time.rs:121
  27:     0x55d9761e74db - layout_thread::{{impl}}::handle_request_helper
                        at components/layout_thread/lib.rs:667
  28:     0x55d9761e64c5 - layout_thread::{{impl}}::handle_request
                        at components/layout_thread/lib.rs:639
  29:     0x55d9761e5709 - layout_thread::{{impl}}::start
                        at components/layout_thread/lib.rs:557
  30:     0x55d9761e2f13 - layout_thread::{{impl}}::create::{{closure}}::{{closure}}
                        at components/layout_thread/lib.rs:290
  31:     0x55d97611979c - profile_traits::mem::{{impl}}::run_with_memory_reporting<closure,fn(profile_traits::mem::ReportsChan) -> script_layout_interface::message::Msg,script_layout_interface::message::Msg,std::sync::mpsc::Sender<script_layout_interface::message::Msg>>
                        at components/profile_traits/mem.rs:63
  32:     0x55d9763b72d4 - layout_thread::{{impl}}::create::{{closure}}
                        at components/layout_thread/lib.rs:289
  33:     0x55d9762a8ada - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  34:     0x55d976144053 - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  35:     0x55d9760d958a - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  36:     0x55d976144ef9 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  37:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  38:     0x55d97614482c - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  39:     0x55d976143c75 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  40:     0x55d9762a9f3e - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  41:     0x55d9763096b3 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  42:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  43:     0x7fc9ef1e16b9 - start_thread
  44:     0x7fc9eed013dc - clone
  45:                0x0 - <unknown>
IpcSelectionResult::unwrap(): channel 1 closed (thread ResourceManager, at .cargo/registry/src/github.com-1ecc6299db9ec823/ipc-channel-0.8.0/src/ipc.rs:308)
ERROR:servo: called `Result::unwrap()` on an `Err` value: IoError(Error { repr: Os { code: 104, message: "Connection reset by peer" } })
Stack trace for thread "CanvasThread"
stack backtrace:
   0:     0x55d97bdce814 - backtrace::backtrace::libunwind::trace
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/libunwind.rs:53
                         - backtrace::backtrace::trace<closure>
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/backtrace/mod.rs:42
   1:     0x55d97bdc7aff - backtrace::capture::{{impl}}::new
                        at .cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.2/src/capture.rs:64
   2:     0x55d9759d9d81 - servo::install_crash_handler::handler
                        at ports/servo/main.rs:71
   3:     0x7fc9eec2f4af - <unknown>
   4:     0x55d97be66b6b - std::panicking::rust_panic_with_hook
                        at /checkout/src/libstd/panicking.rs:562
   5:     0x55d97be66964 - std::panicking::begin_panic<alloc::string::String>
                        at /checkout/src/libstd/panicking.rs:511
   6:     0x55d97be668f9 - std::panicking::begin_panic_fmt
                        at /checkout/src/libstd/panicking.rs:495
   7:     0x55d97be66887 - std::panicking::rust_begin_panic
                        at /checkout/src/libstd/panicking.rs:471
   8:     0x55d97be9576d - core::panicking::panic_fmt
                        at /checkout/src/libcore/panicking.rs:71
   9:     0x55d97b7dcbbc - core::result::unwrap_failed<alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/macros.rs:29
  10:     0x55d97b7944c7 - core::result::{{impl}}::unwrap<(),alloc::boxed::Box<bincode::internal::ErrorKind>>
                        at /checkout/src/libcore/result.rs:738
  11:     0x55d97b7a33fe - webrender_api::api::{{impl}}::delete_image
                        at .cargo/git/checkouts/webrender-c3596abe1cf4f320/33e6e28/webrender_api/src/api.rs:266
  12:     0x55d9774fc651 - canvas::canvas_paint_thread::{{impl}}::drop
                        at components/canvas/canvas_paint_thread.rs:749
  13:     0x55d977421a84 - core::ptr::drop_in_place<canvas::canvas_paint_thread::CanvasPaintThread>
                        at /checkout/src/libcore/ptr.rs:60
  14:     0x55d977431248 - canvas::canvas_paint_thread::{{impl}}::start::{{closure}}
                        at components/canvas/canvas_paint_thread.rs:215
  15:     0x55d977419702 - std::sys_common::backtrace::__rust_begin_short_backtrace<closure,()>
                        at /checkout/src/libstd/sys_common/backtrace.rs:136
  16:     0x55d977478a0a - std::thread::{{impl}}::spawn::{{closure}}::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:364
  17:     0x55d9774336e2 - std::panic::{{impl}}::call_once<(),closure>
                        at /checkout/src/libstd/panic.rs:296
  18:     0x55d9773f96c2 - std::panicking::try::do_call<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panicking.rs:454
  19:     0x55d97be6dc3c - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
  20:     0x55d9773f9225 - std::panicking::try<(),std::panic::AssertUnwindSafe<closure>>
                        at /checkout/src/libstd/panicking.rs:433
  21:     0x55d977477439 - std::panic::catch_unwind<std::panic::AssertUnwindSafe<closure>,()>
                        at /checkout/src/libstd/panic.rs:361
  22:     0x55d977478831 - std::thread::{{impl}}::spawn::{{closure}}<closure,()>
                        at /checkout/src/libstd/thread/mod.rs:363
  23:     0x55d977498c07 - alloc::boxed::{{impl}}::call_box<(),closure>
                        at /checkout/src/liballoc/boxed.rs:652
  24:     0x55d97be6558b - alloc::boxed::{{impl}}::call_once<(),()>
                        at /checkout/src/liballoc/boxed.rs:662
                         - std::sys_common::thread::start_thread
                        at /checkout/src/libstd/sys_common/thread.rs:21
                         - std::sys::imp::thread::{{impl}}::new::thread_start
                        at /checkout/src/libstd/sys/unix/thread.rs:84
  25:     0x7fc9ef1e16b9 - start_thread
  26:     0x7fc9eed013dc - clone
  27:                0x0 - <unknown>
Servo exited with return value -4

[dralley]

@jdm this can be closed, it gets through the first test fine, it doesn't crash until somewhere after test 4 (several of them don't render at all so it's hard to know which test is which)