Re: [PATCH] android: binder: fix type mismatch warning

From: Arnd Bergmann
Date: Mon Sep 18 2017 - 11:35:10 EST


On Mon, Sep 18, 2017 at 4:02 PM, Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>> However, there is another problem with the Kconfig option: turning
>> it on or off creates two incompatible ABI versions, a kernel that
>> has this enabled cannot run user space that was built without it
>> or vice versa. A better solution might be to leave the option hidden
>> until the binder code is fixed to deal with both ABI versions.
>
> I don't know if that is ever going to be fixed, as it's not an issue
> that you will ever see "in the wild" from what I can tell...

Probably not on a native Android device or even a Chromebook that
ships a binder user space together with a kernel, but what about
people using "anbox" or similar projects that allow you to run
Android apps in a container?

It seems like a legitimate use case of the binder modules, but
now there is a kernel Kconfig option that has to match a user
space binary.

Arnd