Segmentation fault on subsequent conversions

[jonatanklosko]

Hello, thank you for this fantastic package!

The following modified example from vl-convert-rs results in a segfault:

use vl_convert_rs::converter::VlOpts;
use vl_convert_rs::{VlConverter, VlVersion};

#[tokio::main]
async fn main() {
    let vl_spec: serde_json::Value = serde_json::from_str(
        r#"
{
  "$schema": "https://vega.github.io/schema/vega-lite/v5.json",
  "data": {"url": "data/movies.json"},
  "mark": "circle",
  "encoding": {
    "x": {
      "bin": {"maxbins": 10},
      "field": "IMDB Rating"
    },
    "y": {
      "bin": {"maxbins": 10},
      "field": "Rotten Tomatoes Rating"
    },
    "size": {"aggregate": "count"}
  }
}   "#,
    )
    .unwrap();


    println!("{}", convert(vl_spec.clone()).await);
    println!("{}", convert(vl_spec.clone()).await)
}

async fn convert(vl_spec: serde_json::Value) -> String {
  let mut converter = VlConverter::new();

  converter
      .vegalite_to_svg(
          vl_spec,
          VlOpts {
              vl_version: VlVersion::v5_8,
              ..Default::default()
          },
      )
      .await
      .expect("Failed to perform Vega-Lite to Vega conversion")
}

Note a separate converter created for each conversion. If we change it to reuse the same converter it no longer segfaults.

I can reproduce the segfault on x86_64 Ubuntu Linux, running the example directly against vl-convert-rs main.

[jonmmease]

Hi @jonatanklosko, thanks for the report.

Could you give this a try with a "current thread" tokio runtime?

#[tokio::main(flavor = "current_thread")]

Deno isn't fully compatible with the multi-threaded tokio runtime. While not a segfault, here's a prior issue I ran into that was resolved by switching to the single threaded runtime: denoland/deno#19670 (comment)

[jonatanklosko]

@jonmmease unfortunately the segfault still happens :(

[jonatanklosko]

If at all useful, here's the stacktrace obtained via lldb:

Stacktrace

* thread #7, name = 'conversion2', stop reason = unknown crash reason
  * frame #0: 0x00005570f5a01440
    frame #1: 0x000055717583935e conversion2`Builtins_InterpreterEntryTrampoline + 222
    frame #2: 0x00005571758f8d9e conversion2`Builtins_ArrayForEach + 926
    frame #3: 0x000055717583935e conversion2`Builtins_InterpreterEntryTrampoline + 222
    frame #4: 0x000055717583935e conversion2`Builtins_InterpreterEntryTrampoline + 222
    frame #5: 0x0000557175836edc conversion2`Builtins_JSEntryTrampoline + 92
    frame #6: 0x0000557175836c1b conversion2`Builtins_JSEntry + 155
    frame #7: 0x00005571751418d4 conversion2`v8::internal::(anonymous namespace)::Invoke(v8::internal::Isolate*, v8::internal::(anonymous namespace)::InvokeParams const&) at execution.cc:420:22
    frame #8: 0x0000557175141f5e conversion2`v8::internal::Execution::CallScript(v8::internal::Isolate*, v8::internal::Handle<v8::internal::JSFunction>, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>) at execution.cc:517:10
    frame #9: 0x00005571750a1f44 conversion2`v8::Script::Run(v8::Local<v8::Context>, v8::Local<v8::Data>) at api.cc:2143:7
    frame #10: 0x0000557174a5b9e7 conversion2`v8::script::_$LT$impl$u20$v8..data..Script$GT$::run::_$u7b$$u7b$closure$u7d$$u7d$::h2a8df6e375005345((null)={closure_env#0} @ 0x00007fa60868db88, sd=0x00007fa5ec300430) at script.rs:99:29
    frame #11: 0x0000557174c05580 conversion2`v8::script::_$LT$impl$u20$v8..data..Script$GT$::run::ha294ac49edf3f9e9 [inlined] v8::scope::HandleScope$LT$$LP$$RP$$GT$::cast_local::ha62ff887adee9464(self=0x00007fa60868ff40, f={closure_env#0} @ 0x00007fa60868dc90) at scope.rs:253:21
    frame #12: 0x0000557174c05234 conversion2`v8::script::_$LT$impl$u20$v8..data..Script$GT$::run::ha294ac49edf3f9e9(self=0x00007fa5ec7dc420, scope=0x00007fa60868ff40) at script.rs:99
    frame #13: 0x0000557174a9cc1e conversion2`deno_core::runtime::bindings::initialize_primordials_and_infra::hffe0cdfcfa9b18da(scope=0x00007fa60868ff40) at bindings.rs:319:5
    frame #14: 0x00005571749a3f32 conversion2`deno_core::runtime::jsruntime::JsRuntime::new_inner::hc1b5c5a1e2e61d5a(options=RuntimeOptions @ 0x00007fa6086910d0, will_snapshot=false) at jsruntime.rs:1002:7
    frame #15: 0x00005571749a02bf conversion2`deno_core::runtime::jsruntime::JsRuntime::try_new::hecb9dbbc76ac4a2c(options=RuntimeOptions @ 0x00007fa608694cb0) at jsruntime.rs:738:5
    frame #16: 0x00005571749a004c conversion2`deno_core::runtime::jsruntime::JsRuntime::new::h7caf829e38686389(options=<unavailable>) at jsruntime.rs:721:11
    frame #17: 0x000055716f84af00 conversion2`deno_runtime::worker::MainWorker::from_options::ha37d25136b4b9f12(main_module=Url @ 0x00007fa608698090, permissions=PermissionsContainer @ 0x00007fa608692538, options=WorkerOptions @ 0x00007fa6086980e8) at worker.rs:487:26
    frame #18: 0x000055716f84852e conversion2`deno_runtime::worker::MainWorker::bootstrap_from_options::hc11b349e74c8a31a(main_module=Url @ 0x00007fa608699660, permissions=PermissionsContainer @ 0x00007fa608697e08, options=WorkerOptions @ 0x00007fa6086996b8) at worker.rs:313:22
    frame #19: 0x000055716ec7f62f conversion2`vl_convert_rs::converter::InnerVlConverter::try_new::_$u7b$$u7b$closure$u7d$$u7d$::he49ddb4d43884203((null)=0x00007fa60869db70) at converter.rs:589:13
    frame #20: 0x000055716ec8ba81 conversion2`vl_convert_rs::converter::VlConverter::new::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h0e25bbd3090b7868((null)=0x00007fa60869db70) at converter.rs:1027:61
    frame #21: 0x000055716ecb4320 conversion2`tokio::runtime::scheduler::current_thread::CurrentThread::block_on::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::hd5f5af96aa029794(cx=0x00007fa60869db70) at mod.rs:186:49
    frame #22: 0x000055716ecb37b1 conversion2`_$LT$tokio..future..poll_fn..PollFn$LT$F$GT$$u20$as$u20$core..future..future..Future$GT$::poll::hb47777a9101694ab(self=Pin<&mut tokio::future::poll_fn::PollFn<tokio::runtime::scheduler::current_thread::{impl#0}::block_on::{closure#0}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure#0}::{async_block_env#0}>>> @ 0x00007fa60869da68, cx=0x00007fa60869db70) at poll_fn.rs:58:9
    frame #23: 0x000055716ecbebd7 conversion2`tokio::runtime::park::CachedParkThread::block_on::_$u7b$$u7b$closure$u7d$$u7d$::hfe7daf12fe9a5c02 at park.rs:281:63
    frame #24: 0x000055716ecbe4ae conversion2`tokio::runtime::park::CachedParkThread::block_on::h79c0d261a58330cc at coop.rs:107:5
    frame #25: 0x000055716ecbe423 conversion2`tokio::runtime::park::CachedParkThread::block_on::h79c0d261a58330cc [inlined] tokio::runtime::coop::budget::ha88d84af0f46c8fd(f={closure_env#0}<tokio::future::poll_fn::PollFn<tokio::runtime::scheduler::current_thread::{impl#0}::block_on::{closure#0}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure#0}::{async_block_env#0}>>> @ 0x00007fa60869dc20) at coop.rs:73
    frame #26: 0x000055716ecbe384 conversion2`tokio::runtime::park::CachedParkThread::block_on::h79c0d261a58330cc(self=0x00007fa60869dc96, f=PollFn<tokio::runtime::scheduler::current_thread::{impl#0}::block_on::{closure#0}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure#0}::{async_block_env#0}>> @ 0x00007fa60869dbc8) at park.rs:281
    frame #27: 0x000055716ecbc958 conversion2`tokio::runtime::context::blocking::BlockingRegionGuard::block_on::h77af11f419231fe4(self=0x00007fa60869def0, f=PollFn<tokio::runtime::scheduler::current_thread::{impl#0}::block_on::{closure#0}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure#0}::{async_block_env#0}>> @ 0x00007fa60869dca0) at blocking.rs:66:9
    frame #28: 0x000055716ecb4100 conversion2`tokio::runtime::scheduler::current_thread::CurrentThread::block_on::_$u7b$$u7b$closure$u7d$$u7d$::h500fa7a704f42916(blocking=0x00007fa60869def0) at mod.rs:180:40
    frame #29: 0x000055716ecb7f5e conversion2`tokio::runtime::context::runtime::enter_runtime::hf1b95be7488a0148(handle=0x00005571794f3098, allow_block_in_place=false, f={closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure#0}::{async_block_env#0}> @ 0x00007fa60869e770) at runtime.rs:65:16
    frame #30: 0x000055716ecb3a91 conversion2`tokio::runtime::scheduler::current_thread::CurrentThread::block_on::hf07e103c654ad87b(self=0x00005571794f3070, handle=0x00005571794f3098, future=<unavailable>) at mod.rs:167:9
    frame #31: 0x000055716ec95dc8 conversion2`tokio::runtime::runtime::Runtime::block_on::h2ed773bfebfabae4(self=0x00005571794f3068, future={async_block_env#0} @ 0x00007fa60869f880) at runtime.rs:348:47
    frame #32: 0x000055716ec8b6eb conversion2`vl_convert_rs::converter::VlConverter::new::_$u7b$$u7b$closure$u7d$$u7d$::h9ea1b1e7d28fd52f at converter.rs:1026:13
    frame #33: 0x000055716ecae8bd conversion2`std::sys::backtrace::__rust_begin_short_backtrace::hcd778ea3610c22e8(f={closure_env#0} @ 0x00007fa6086a0090) at backtrace.rs:154:18
    frame #34: 0x000055716eca721b conversion2`std::thread::Builder::spawn_unchecked_::_$u7b$$u7b$closure$u7d$$u7d$::_$u7b$$u7b$closure$u7d$$u7d$::h634919b9f26751be at mod.rs:538:17
    frame #35: 0x000055716ecbd65f conversion2`_$LT$core..panic..unwind_safe..AssertUnwindSafe$LT$F$GT$$u20$as$u20$core..ops..function..FnOnce$LT$$LP$$RP$$GT$$GT$::call_once::h6665d0ca04b7d1d5(self=AssertUnwindSafe<std::thread::{impl#0}::spawn_unchecked_::{closure#1}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure_env#0}, core::result::Result<(), anyhow::Error>>> @ 0x00007fa6086a00c8, (null)=<unavailable>) at unwind_safe.rs:272:9
    frame #36: 0x000055716ecbbc3a conversion2`std::panicking::try::do_call::h6370f39536327d9d(data="�,{qU") at panicking.rs:557:40
    frame #37: 0x000055716eca723b conversion2`__rust_try + 27
    frame #38: 0x000055716eca6e44 conversion2`std::thread::Builder::spawn_unchecked_::_$u7b$$u7b$closure$u7d$$u7d$::ha91f5cdbe853a4d4 at panicking.rs:520:19
    frame #39: 0x000055716eca6e11 conversion2`std::thread::Builder::spawn_unchecked_::_$u7b$$u7b$closure$u7d$$u7d$::ha91f5cdbe853a4d4 [inlined] std::panic::catch_unwind::h48d45f508bfc1507(f=AssertUnwindSafe<std::thread::{impl#0}::spawn_unchecked_::{closure#1}::{closure_env#0}<vl_convert_rs::converter::{impl#7}::new::{closure_env#0}, core::result::Result<(), anyhow::Error>>> @ 0x00007fa6086a0330) at panic.rs:358
    frame #40: 0x000055716eca6e11 conversion2`std::thread::Builder::spawn_unchecked_::_$u7b$$u7b$closure$u7d$$u7d$::ha91f5cdbe853a4d4 at mod.rs:537
    frame #41: 0x000055716ec4b3ff conversion2`core::ops::function::FnOnce::call_once$u7b$$u7b$vtable.shim$u7d$$u7d$::hd8e5a4833b9a7aa9((null)=0x000055717b052cb0, (null)=<unavailable>) at function.rs:250:5
    frame #42: 0x000055717670437b conversion2`std::sys::pal::unix::thread::Thread::new::thread_start::hcc78f3943333fa94 [inlined] _$LT$alloc..boxed..Box$LT$F$C$A$GT$$u20$as$u20$core..ops..function..FnOnce$LT$Args$GT$$GT$::call_once::hf75717d9f28faebf at boxed.rs:2454:9
    frame #43: 0x0000557176704373 conversion2`std::sys::pal::unix::thread::Thread::new::thread_start::hcc78f3943333fa94 [inlined] _$LT$alloc..boxed..Box$LT$F$C$A$GT$$u20$as$u20$core..ops..function..FnOnce$LT$Args$GT$$GT$::call_once::h7bd883a5f3c5f3c1 at boxed.rs:2454
    frame #44: 0x000055717670436c conversion2`std::sys::pal::unix::thread::Thread::new::thread_start::hcc78f3943333fa94 at thread.rs:105
    frame #45: 0x00007fa60a6b8609 libpthread.so.0`start_thread + 217
    frame #46: 0x00007fa60a48c353 libc.so.6`__clone + 67

[jonmmease]

Thanks for the stack trace.

I don't see the crash when running this example locally on macos, so I tried running it in a GitHub action under Ubuntu 22.04, and I still don't see the crash. See #207 and https://github.com/vega/vl-convert/actions/runs/12483749003/job/34840040408?pr=207.

A helpful next step would be to get a repro of this in a GitHub actions, so let me know if you have any thoughts on what we could try here.

[jonatanklosko]

It looks like I cannot reproduce it on GitHub Actions, I used a minimal setup:

jobs:
  vl-convert-rs-example2:
    runs-on: ubuntu-20.04
    container:
      image: ubuntu:22.04
    steps:
      - uses: actions/checkout@v2
      - run: |
          apt-get update
          apt-get install -y git build-essential wget curl
          curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
          . "$HOME/.cargo/env"
          cd vl-convert-rs
          cargo run --example conversion_sequence

I can reproduce the segfault running exactly that code on AWS x86_64 machine with Ubuntu 20.04, and I also run inside ubuntu:22.04 Docker container in both cases, just to make the setup is as close as possible. I don't know what else can be at play.