fix

youknowone · youknowone · commit ecb9b4cf162d · 2026-01-11T21:14:34.000+09:00
diff --git a/crates/vm/src/stdlib/posix.rs b/crates/vm/src/stdlib/posix.rs
@@ -677,8 +677,13 @@ pub mod module {
 
     /// Warn if forking from a multi-threaded process
     fn warn_if_multi_threaded(name: &str, vm: &VirtualMachine) {
-        // Check threading._active and threading._limbo to count threads
-        let threading = match vm.import("threading", 0) {
+        // Only check threading if it was already imported
+        // Avoid vm.import() which can execute arbitrary Python code in the fork path
+        let threading = match vm
+            .sys_module
+            .get_attr("modules", vm)
+            .and_then(|m| m.get_item("threading", vm))
+        {
             Ok(m) => m,
             Err(_) => return,
         };
diff --git a/crates/vm/src/stdlib/thread.rs b/crates/vm/src/stdlib/thread.rs
@@ -485,11 +485,13 @@ pub(crate) mod _thread {
             };
 
             match handle_to_join {
-                Some((inner, done_event)) => {
+                Some((_inner, done_event)) => {
                     // Wait for this thread to finish (infinite timeout)
+                    // Only check done flag to avoid lock ordering issues
+                    // (done_event lock vs inner lock)
                     let (lock, cvar) = &*done_event;
                     let mut done = lock.lock();
-                    while !*done && inner.lock().state != ThreadHandleState::Done {
+                    while !*done {
                         cvar.wait(&mut done);
                     }
                 }
@@ -534,11 +536,14 @@ pub(crate) mod _thread {
 
     // Store the main thread ident (initialized at VM startup)
     static MAIN_THREAD_IDENT: AtomicCell<u64> = AtomicCell::new(0);
+    static MAIN_THREAD_INIT: std::sync::Once = std::sync::Once::new();
 
     /// Initialize the main thread ident. Should be called once at interpreter startup.
     pub fn init_main_thread_ident() {
-        let ident = get_ident();
-        MAIN_THREAD_IDENT.store(ident);
+        MAIN_THREAD_INIT.call_once(|| {
+            let ident = get_ident();
+            MAIN_THREAD_IDENT.store(ident);
+        });
     }
 
     /// ExceptHookArgs - simple class to hold exception hook arguments
@@ -687,9 +692,11 @@ pub(crate) mod _thread {
 
     impl Drop for LocalGuard {
         fn drop(&mut self) {
-            // eprintln!("[DEBUG] LocalGuard::drop called for thread {:?}", self.thread_id);
             if let Some(local_data) = self.local.upgrade() {
-                local_data.data.lock().remove(&self.thread_id);
+                // Remove from map while holding the lock, but drop the value
+                // outside the lock to prevent deadlock if __del__ accesses _local
+                let removed = local_data.data.lock().remove(&self.thread_id);
+                drop(removed);
             }
         }
     }
@@ -961,14 +968,15 @@ pub(crate) mod _thread {
             }
 
             // Wait for thread completion using Condvar (supports timeout)
+            // Loop to handle spurious wakeups
             let (lock, cvar) = &*self.done_event;
             let mut done = lock.lock();
 
-            if !*done {
+            while !*done {
                 if let Some(timeout) = timeout_duration {
                     let result = cvar.wait_for(&mut done, timeout);
-                    if result.timed_out() {
-                        // Timeout occurred, return without joining
+                    if result.timed_out() && !*done {
+                        // Timeout occurred and done is still false
                         return Ok(());
                     }
                 } else {
@@ -1100,6 +1108,10 @@ pub(crate) mod _thread {
                             unsafe { lock.mu.unlock() };
                         }
                     }
+
+                    // Clean up thread-local data while VM context is still active
+                    cleanup_thread_local_data();
+
                     vm_state.thread_count.fetch_sub(1);
                 }
 
