Node SEA with useSnapshot cannot start worker thread

[nomagick]

Version

v22.11.0

Platform

Darwin Mac.lan 24.1.0 Darwin Kernel Version 24.1.0: Thu Oct 10 21:03:11 PDT 2024; root:xnu-11215.41.3~2/RELEASE_ARM64_T6020 arm64

Subsystem

sea

What steps will reproduce the bug?

Generate a SEA and start a worker thread in it

How often does it reproduce? Is there a required condition?

Always

What is the expected behavior? Why is that the expected behavior?

Thread can be started.

What do you see instead?

Native stack trace

Additional information

  #  ./out.bin[76089]: MaybeLocal<v8::Value> node::StartExecution(node::Environment *, node::StartExecutionCallback) at ../src/node.cc:378
  #  Assertion failed: !(sea.use_snapshot()) || (!env->snapshot_deserialize_main().IsEmpty())

----- Native stack trace -----

 1: 0x1006b3778 node::Assert(node::AssertionInfo const&) [/Users/yanlong.wang/out.bin]
 2: 0x1022b7664 node::StartExecution(node::Environment*, std::__1::function<v8::MaybeLocal<v8::Value> (node::StartExecutionCallbackInfo const&)>) (.cold.1) [/Users/yanlong.wang/out.bin]
 3: 0x10066dc04 node::StartExecution(node::Environment*, std::__1::function<v8::MaybeLocal<v8::Value> (node::StartExecutionCallbackInfo const&)>) [/Users/yanlong.wang/out.bin]
 4: 0x1005d6460 node::LoadEnvironment(node::Environment*, std::__1::function<v8::MaybeLocal<v8::Value> (node::StartExecutionCallbackInfo const&)>, std::__1::function<void (node::Environment*, v8::Local<v8::Value>, v8::Local<v8::Value>)>) [/Users/yanlong.wang/out.bin]
 5: 0x1007a48bc node::worker::Worker::Run() [/Users/yanlong.wang/out.bin]
 6: 0x1007a8b0c node::worker::Worker::StartThread(v8::FunctionCallbackInfo<v8::Value> const&)::$_3::__invoke(void*) [/Users/yanlong.wang/out.bin]
 7: 0x192a832e4 _pthread_start [/usr/lib/system/libsystem_pthread.dylib]
 8: 0x192a7e0fc thread_start [/usr/lib/system/libsystem_pthread.dylib]
[1]    76089 abort      ./out.bin

[nomagick]

This also breaks the esm loader hooks because it also runs in a thread.

[nomagick]

Looks like here:

node/src/node.cc

Lines 322 to 350 in 03ec900

	#ifndef DISABLE_SINGLE_EXECUTABLE_APPLICATION
	if (sea::IsSingleExecutable()) {
	sea::SeaResource sea = sea::FindSingleExecutableResource();
	// The SEA preparation blob building process should already enforce this,
	// this check is just here to guard against the unlikely case where
	// the SEA preparation blob has been manually modified by someone.
	CHECK_IMPLIES(sea.use_snapshot(),
	!env->snapshot_deserialize_main().IsEmpty());
	}
	#endif
	// Ignore env file if we're in watch mode.
	// Without it env is not updated when restarting child process.
	// Child process has --watch flag removed, so it will load the file.
	if (env->options()->has_env_file_string && !env->options()->watch_mode) {
	per_process::dotenv_file.SetEnvironment(env);
	}
	// TODO(joyeecheung): move these conditions into JS land and let the
	// deserialize main function take precedence. For workers, we need to
	// move the pre-execution part into a different file that can be
	// reused when dealing with user-defined main functions.
	if (!env->snapshot_deserialize_main().IsEmpty()) {
	return env->RunSnapshotDeserializeMain();
	}
	if (env->worker_context() != nullptr) {
	return StartExecution(env, "internal/main/worker_thread");
	}

[joyeecheung]

Hmm, looks like we just need to skip the SEA stuff for worker threads during bootstrap, since that's meant for the main thread anyway.