[PATCH v9 0/18] MR10569: wineandroid: rework Android integration and switch to split process model

April 15, 2026

      This series reworks the wineandroid driver and moves it away from the
current “Wine inside JVM process” model to a split architecture where
the Android activity (UI) and Wine run in separate processes.

The existing model relies on running Wine inside the JVM process and
interacting with Android through JNI callbacks and APC/unixlib-based
dispatch. This approach no longer works reliably on modern Android:

- Android 10+ applies seccomp restrictions to app processes, making a
  number of required syscalls unavailable inside the activity process,
  while processes started via fork/exec are not subject to the same
  limitations.

- The implementation depends on Wine thread context (TEB), signal
  handling, and register state assumptions that conflict with the JVM
  runtime (e.g. segment register usage on x86), requiring fragile
  workarounds.

- Due to sandboxing, it is difficult to reliably debug or even observe
  all failure modes, and future Android changes are likely to tighten
  these restrictions further.

At the same time, downstream projects such as MiceWine, Winlator,
Termux’s Wine environment, GameHub and GameNative already use a model
where the UI (activity) and Wine run in separate processes and
communicate via IPC, which has proven to work reliably on current
Android systems.

This series implements that model in wineandroid:

- Wine is now started in a separate process via fork/exec instead of
  running inside the JVM process.

- Android-facing code no longer depends on the Wine APC/unixlib execution
  path and runs on the UI thread where appropriate (e.g. native window
  registration).

- ioctl handling is reworked to remove reliance on Wine thread context,
  with explicit JNIEnv usage and fd-based reply plumbing.

- Environment setup and initialization are moved to the Java side,
  simplifying the native startup path.

- Logging for ioctl paths is routed through Android logcat without
  depending on a Wine TEB.

The changes are split into multiple bisect-safe commits to keep
intermediate states functional while migrating the code step by step.

With Wine running in a separate process, it is no longer subject to JVM
seccomp restrictions, and there are no longer conflicts between JVM and
Wine execution contexts (signals, thread state, register usage, etc.).

<details>
<summary>Old message</summary>

wineandroid: move ioctl handling to dedicated Java-only thread

Move ioctl handling out of the Wine APC/unixlib execution path into a
dedicated Java-only thread without Wine context.

On Android 10+ a number of syscalls are restricted inside the activity
process via seccomp, while processes started via fork/exec are not
subject to the same limitations. Decoupling ioctl handling from the
Wine context is required to eventually run this code outside of the
activity process.

This change introduces a new transport and execution model where ioctl
dispatch no longer depends on Wine thread state, preparing for moving
the Android backend into a separate process.

The refactor is intentionally split into multiple bisect-safe commits
to keep intermediate states functional while gradually migrating the
dispatch path.

Since this is a fairly large chunk of work, I’d like to make sure we’re aligned before continuing.

</details>

--
  v9: wineandroid: split Android driver and Wine into separate processes
      wineandroid: make JNI initialization work with direct JVM loading
      wineandroid: create desktop view via ioctl and pass event pipe
      wineandroid: return ioctl errors directly
      wineandroid: remove unixlib/ntoskrnl ioctl path
      wineandroid: switch dequeueBuffer to socket transport
      wineandroid: switch ioctl dispatch to socket transport on main thread looper
      wineandroid: pass JNIEnv explicitly through ioctl handlers
      wineandroid: add reply_fd plumbing to ioctl path
      wineandroid: move native window registration to surface_changed
      wineandroid: simplify client pid handling
      wineandroid: use Android logging for ioctl dispatch paths
      wineandroid: load AHardwareBuffer symbols from libandroid
      wineandroid: switch java_* variables to direct linking
      wineandroid: set environment in Java and simplify wine_init
      wineandroid: fix loader path and library lookup for modern Wine/Android
      wineandroid: lower targetSdkVersion to avoid Android 10 W^X restrictions
      wineandroid: fix 64-bit crash in setCursor JNI call

This merge request has too many patches to be relayed via email.
Please visit the URL below to see the contents of the merge request.
https://gitlab.winehq.org/wine/wine/-/merge_requests/10569

Twaik Yont (＠twaik)

Twaik Yont (＠twaik)

tags

participants (1)