8992b99b - trap on blocking call in sync task before return (#12043)

Tue, 09 Dec 2025 15:41:57 +0000

trap on blocking call in sync task before return (#12043)* trap on blocking call in sync task before returnThis implements a spec change (PR pending) such that tasks created for calls tosynchronous exports may not call potentially-blocking imports or return `wait`or `poll` callback codes prior to returning a value. Specifically, thefollowing are prohibited in that scenario:- returning callback-code.{wait,poll}- sync calling an async import- sync calling subtask.cancel- sync calling {stream,future}.{read,write}- sync calling {stream,future}.cancel-{read,write}- calling waitable-set.{wait,poll}- calling thread.suspendThis breaks a number of tests, which will be addressed in follow-up commits:- The `{tcp,udp}-socket.bind` implementation in `wasmtime-wasi` is implemented using `Linker::func_wrap_concurrent` and thus assumed to be async, whereas the WIT interface says they're sync, leading to a type mismatch error at runtime. Alex and I have discussed this and have a general plan to address it.- A number of tests in the tests/component-model submodule that points to the spec repo are failing. Those will presumably be fixed as part of the upcoming spec PR (although some could be due to bugs in this implementation, in which case I'll fix them).- A number of tests in tests/misc_testsuite are failing. I'll address those in a follow-up commit.Signed-off-by: Joel Dice * call `check_may_leave` before `check_blocking``check_blocking` needs access to the current task, but that's not set forpost-return functions since those should not be calling _any_ imports at all, sofirst check for that.Signed-off-by: Joel Dice * fix `misc_testsuite` test regressionsThis amounts to adding `async` to any exported component functions that mightneed to block.Signed-off-by: Joel Dice * simplify code in `ConcurrentState::check_blocking`Signed-off-by: Joel Dice * make `thread.yield` a no-op in non-blocking contextsPer the proposed spec changes, `thread.yield` should return control to the guestimmediately without allowing any other thread to run. Similarly, when anasync-lifted export or callback returns `CALLBACK_CODE_YIELD`, we should callthe callback again immediately without allowing another thread to run.Signed-off-by: Joel Dice * fix build when `component-model-async` feature disabledSigned-off-by: Joel Dice * fix more test regressionsSigned-off-by: Joel Dice * fix more test regressionsNote that this temporarily updates the `tests/component-model` submodule to thebranch for https://github.com/WebAssembly/component-model/pull/577 until that PRis merged.Signed-off-by: Joel Dice * tweak `Trap::CannotBlockSyncTask` messageThis clarifies that such a task cannot block prior to returning.Signed-off-by: Joel Dice * fix cancel_host_future testSigned-off-by: Joel Dice * trap sync-lowered, guest->guest async calls in sync tasksI somehow forgot to address this earlier. Thanks to Luke for catching this.Note that this commit doesn't include test coverage, but Luke's forthecomingtests in the `component-model` repo will cover it, and we'll pull that in withthe next submodule update.Signed-off-by: Joel Dice * switch back to `main` branch of `component-model` repo...and skip or `should_fail` the tests that won't pass untilhttps://github.com/WebAssembly/component-model/pull/578 is merged.Signed-off-by: Joel Dice * add `trap-if-block-and-sync.wast`We'll remove this again in favor of the upstream version oncehttps://github.com/WebAssembly/component-model/pull/578 has been merged.Signed-off-by: Joel Dice * address review feedback- Assert that `StoreOpaque::suspend` is not called in a non-blocking context except in specific circumstances- Typecheck async-ness for dynamic host functions- Use type parameter instead of value parameter in `call_host[_dynamic]`Signed-off-by: Joel Dice * add explanation comments to `check_blocking` callsSigned-off-by: Joel Dice * fix fuzz test oracle for async functionsSigned-off-by: Joel Dice ---------Signed-off-by: Joel Dice List of files: /wasmtime-44.0.1/crates/test-programs/src/bin/async_read_resource_stream.rs

804060c8 - add Component Model async ABI tests (#11136)

Fri, 11 Jul 2025 23:32:19 +0000

add Component Model async ABI tests (#11136)* add Component Model async ABI testsThis pulls in the tests from the `wasip3-prototyping` repo, minus the onesrequiring WASIp3 support in `wasmtime-wasi[-http]`, which will be PR'dseparately.* add audits and exemptions for new `component-async-tests` depsIn order to convince `cargo vet` that we only needed these deps to be`safe-to-run` (not necessarily `safe-to-deploy`, since it's test code), I'vemoved the `wasm-compose` dep to the `dev-dependencies` section of the`Cargo.toml` file, which required rearranging some code.I've exempted `wasm-compose` since it's a BA project, and also exempted all butone of the remaining new deps since they each get well over 10,000 downloads perday from crates.io. I've audited and certified the remaining dep, `im-rc`,which came in a bit shy of the 10,000-per-day mark.Signed-off-by: Joel Dice * simplify `component_async_tests::util::sleep`Signed-off-by: Joel Dice ---------Signed-off-by: Joel Dice List of files: /wasmtime-44.0.1/crates/test-programs/src/bin/async_read_resource_stream.rs

Changes in async_read_resource_stream.rs

8992b99b - trap on blocking call in sync task before return (#12043)

804060c8 - add Component Model async ABI tests (#11136)