failed to open synthetic bubblewrap mount registry lock {}:

Error message

failed to open synthetic bubblewrap mount registry lock {}: {err}

What it means

Error "failed to open synthetic bubblewrap mount registry lock {}: {err}" thrown in openai/codex.

Source

Thrown at codex-rs/linux-sandbox/src/linux_run_main.rs:1309

}

fn with_synthetic_mount_registry_lock<T>(f: impl FnOnce() -> T) -> T {
    let registry_root = synthetic_mount_registry_root();
    fs::create_dir_all(&registry_root).unwrap_or_else(|err| {
        panic!(
            "failed to create synthetic bubblewrap mount registry {}: {err}",
            registry_root.display()
        )
    });
    let lock_path = registry_root.join("lock");
    let lock_file = OpenOptions::new()
        .read(true)
        .write(true)
        .create(true)
        .truncate(false)
        .open(&lock_path)
        .unwrap_or_else(|err| {
            panic!(
                "failed to open synthetic bubblewrap mount registry lock {}: {err}",
                lock_path.display()
            )
        });
    if unsafe { libc::flock(lock_file.as_raw_fd(), libc::LOCK_EX) } < 0 {
        let err = std::io::Error::last_os_error();
        panic!(
            "failed to lock synthetic bubblewrap mount registry {}: {err}",
            lock_path.display()
        );
    }
    let result = f();
    if unsafe { libc::flock(lock_file.as_raw_fd(), libc::LOCK_UN) } < 0 {
        let err = std::io::Error::last_os_error();
        panic!(
            "failed to unlock synthetic bubblewrap mount registry {}: {err}",
            lock_path.display()
        );

View on GitHub (pinned to 339751715c)

When it happens

Trigger: Thrown at codex-rs/linux-sandbox/src/linux_run_main.rs:1309 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of openai/codex@339751715c (2026-08-25). Data as JSON: /api/errors/d408ba785a691310. Report an issue: GitHub.