From 1190b4e38f97023154e6b3bef61b251aa5f970d0 Mon Sep 17 00:00:00 2001 From: Martijn Coenen Date: Fri, 11 May 2018 01:45:24 -0700 Subject: [PATCH] ANDROID: binder: remove 32-bit binder interface. New devices launching with Android P need to use the 64-bit binder interface, even on 32-bit SoCs [0]. This change removes the Kconfig option to select the 32-bit binder interface. We don't think this will affect existing userspace for the following reasons: 1) The latest Android common tree is 4.14, so we don't believe any Android devices are on kernels >4.14. 2) Android devices launch on an LTS release and stick with it, so we wouldn't expect devices running on <= 4.14 now to upgrade to 4.17 or later. But even if they did, they'd rebuild the world (kernel + userspace) anyway. 3) Other userspaces like 'anbox' are already using the 64-bit interface. Note that this change doesn't remove the 32-bit UAPI itself; the reason for that is that Android userspace always uses the latest UAPI headers from upstream, and userspace retains 32-bit support for devices that are upgrading. This will be removed as well in 2-3 years, at which point we can remove the code from the UAPI as well. Finally, this change introduces build errors on archs where 64-bit get_user/put_user is not supported, so make binder unavailable on m68k (which wouldn't want it anyway). [0]: https://android-review.googlesource.com/c/platform/build/+/595193 Signed-off-by: Martijn Coenen Signed-off-by: Greg Kroah-Hartman --- drivers/android/Kconfig | 15 +-------------- drivers/android/binder.c | 4 ---- 2 files changed, 1 insertion(+), 18 deletions(-) diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig index 7dce3795b887..ee4880bfdcdc 100644 --- a/drivers/android/Kconfig +++ b/drivers/android/Kconfig @@ -10,7 +10,7 @@ if ANDROID config ANDROID_BINDER_IPC bool "Android Binder IPC Driver" - depends on MMU + depends on MMU && !M68K default n ---help--- Binder is used in Android for both communication between processes, @@ -32,19 +32,6 @@ config ANDROID_BINDER_DEVICES created. Each binder device has its own context manager, and is therefore logically separated from the other devices. -config ANDROID_BINDER_IPC_32BIT - bool "Use old (Android 4.4 and earlier) 32-bit binder API" - depends on !64BIT && ANDROID_BINDER_IPC - default y - ---help--- - The Binder API has been changed to support both 32 and 64bit - applications in a mixed environment. - - Enable this to support an old 32-bit Android user-space (v4.4 and - earlier). - - Note that enabling this will break newer Android user-space. - config ANDROID_BINDER_IPC_SELFTEST bool "Android Binder IPC Driver Selftest" depends on ANDROID_BINDER_IPC diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 4eab5be3d00f..35f48a39144c 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -72,10 +72,6 @@ #include #include -#ifdef CONFIG_ANDROID_BINDER_IPC_32BIT -#define BINDER_IPC_32BIT 1 -#endif - #include #include "binder_alloc.h" #include "binder_trace.h"