Docker for Mac 起動中には Android Emulator (HAXM) が動かない

下記のようなエラーが出た場合で virtualbox そのものを使っている覚えがない場合で Docker for Mac を使っている場合は Android Emulatror の HAXM ありの場合に起動しない可能性がある。

Hax is enabled
Hax ram_size 0x40000000
HAX is working and emulator runs in fast virt mode.
emulator: Listening for console connections on port: 5554
emulator: Serial number of this emulator (for ADB): emulator-5554
Failed to sync vcpu reg
Failed to sync vcpu reg
Failed to sync vcpu reg
emulator: ERROR: Unfortunately, there's an incompatibility between HAXM hypervisor and VirtualBox 4.3.30+ which doesn't allow multiple hypervisors to co-exist.  It is being actively worked on; you can find out more about the issue at http://b.android.com/197915 (Android) and https://www.virtualbox.org/ticket/14294 (VirtualBox)
Internal error: initial hax sync failed

https://forums.docker.com/t/cant-using-docker-for-mac-with-android-emulator-haxm/8939

対処方法は Docker for Mac を停止させるぐらいしか思いつかない。