Android Emulator (AVD) fails to boot in MacOS

Question

My android emulator fails to boot when the target platform is Level 26 (Android 8.0.0) or higher. The emulator just shows a black screen while the emulator process is constantly running at approx. 100% CPU. Note that level 25 and lower work fine.

Here's what I discovered so far:

I launched the emulator from the command-line so that I can inspect the logcat:

./emulator -avd Test2 -logcat '*:e'

Here's an excerpt from the logcat:

[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 3.18.91+ ([email protected]) (gcc version 4.9 20140827 (prerelease) (GCC) ) #1 SMP PREEMPT Tue Jan 9 20:30:51 UTC 2018
[    0.000000] Command line: qemu=1 androidboot.hardware=ranchu clocksource=pit androidboot.console=ttyS0 android.qemud=1 console=0 console=0 android.checkjni=1 qemu.gles=1 androidboot.logcat=*:e androidboot.selinux=permissive ndns=2 ndns=2
[    0.000000] Disabled fast string operations
... 
(skipping a few hundred lines)
...
[    1.443608] init: init first stage started!
[    1.443608] init: Using Android DT directory /proc/device-tree/firmware/android/
[    1.443608] init: First stage mount skipped (missing/incompatible fstab in device tree)
[    1.453842] init: Skipped setting INIT_AVB_VERSION (not in recovery mode)
[    1.453842] init: Loading SELinux policy
[    1.453842] selinux: SELinux:  Could not open /sepolicy:  No such file or directory
[    1.453842] 
[    1.463161] init: Failed to load monolithic SELinux policy: No such file or directory
[    1.463161] init: panic: rebooting to bootloader
[    1.463161] init: Reboot start, reason: reboot, rebootTarget: bootloader
[    1.472277] init: android::WriteStringToFile open failed: No such file or directory
[    1.472277] init: Shutdown timeout: 6
[    1.472277] init: terminating init services
[    1.472277] init: waitpid failed: No child processes
[    1.482231] init: Terminating running services took 0.013438 seconds with remaining services:0
[    1.482231] init: waitpid failed: No child processes
[    1.482231] init: vold not running, skipping vold shutdown
[    1.607664] init: powerctl_shutdown_time_ms:128:0
[    1.607664] init: Reboot ending, jumping to kernel
[    1.607664] reboot: Restarting system with command 'bootloader'
[    1.607664] reboot: machine restart
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 3.18.91+ ([email protected]) (gcc version 4.9 20140827 (prerelease) (GCC) ) #1 SMP PREEMPT Tue Jan 9 20:30:51 UTC 2018
[    0.000000] Command line: qemu=1 androidboot.hardware=ranchu clocksource=pit androidboot.console=ttyS0 android.qemud=1 console=0 console=0 android.checkjni=1 qemu.gles=1 androidboot.logcat=*:e androidboot.selinux=permissive ndns=2 ndns=2
[    0.000000] Disabled fast string operations
...

This repeats infinitely every 5 seconds. So I suspect my problem has something to do with SELinux. That would make sense, since Android 8 introduced many changes in that area: https://source.android.com/security/selinux/

But I have no clue why others don't have this problem nor what to do about it.

Answer 1

I discovered it was an SELinux issue on the host. This is one way to resolve it:

sudo setsebool -P selinuxuser_execheap 1

There are more specific ways, too. But, you'll want to catch the exception to get the exact command:

Allow this access for now by executing:

ausearch -c 'qemu-system-x86' --raw | audit2allow -M my-qemusystemx86
semodule -X 300 -i my-qemusystemx86.pp

Of course, you can test in general by making SELinux temporarily permissive on your host.

After I did that, the phone display was no longer black.