title: Android Studio emulator: ERROR: detected a hanging thread QEMU2 main loop
body: <p>I use Android Studio 3.0.1 on Ubuntu 16.04. </p>
  
  <p>Yesterday, Android Studio popped up a message saying that there's an update available, and I always click those. It then notified me that it had successfully updated the emulator.</p>
  
  <p>My AVD worked perfectly before, but after the update finished, now when I launch it, it shows a black screen in the emulator window for 15 seconds and then crashes with the following error message:</p>
  
  <pre><code>ERROR: detected a hanging thread 'QEMU2 main loop'. No response for 15000 ms
  Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)
  </code></pre>
  
  <p>I tried the solutions suggested in all the threads describing similar emulator problems. (I verified that the emulator is still installed via the SDK Manager, I tried switching between the software and the hardware graphics settings of the AVD, I tried replacing libstdc++ with a newer version 6.0.24, I tried instead to ln -sf my /usr/lib.. libstdc++ 6.0.21 into the SDK emulator lib64/libstdc++ folder, I even downloaded Android Studio and ran a fresh installation with its own new SDK folder with freshly downloaded SDKs, I tried creating new AVDs with different architectures (arm) and different API levels (24, 27), I tried restarting ADB, and even restarting the computer. Nothing helped.</p>
  
  <p>My SDK tools menu doesn't have an entry for emulator accelerator (HAXM), though my PC has an Intel CPU: I shouldn't have to change this since my AVD worked just yesterday! What broke?</p>
  
  <p>What's causing the 'QEMU2 main loop' to hang, and how can I fix it?</p>