On Wed, 23 Aug 2017 13:48:47 -0500 Rob Herring wrote:

On Tue, Aug 22, 2017 at 9:57 PM, John Stultz [off-list ref] wrote:

quoted

On Tue, Aug 22, 2017 at 7:56 PM, John Stultz [off-list ref] wrote:  

quoted

On Tue, Aug 22, 2017 at 7:34 PM, Jisheng Zhang [off-list ref] wrote:  

quoted

On Tue, 22 Aug 2017 18:51:08 -0700 Greg KH wrote:
 

quoted

On Tue, Aug 08, 2017 at 07:03:05PM +0800, Jisheng Zhang wrote:  

quoted

As noted in commit d0bdff0db809 ("staging: Fix build issues with new
binder API"), we can add back the choice for 32bit ARM "once a 64bit
__get_user_asm_* implementation is merged." Commit e38361d032f1 ("ARM:
8091/2: add get_user() support for 8 byte types") has added the
support, so it's time to let ANDROID_BINDER_IPC_32BIT be selectable on
32bit ARM  

Ok, but:
 

quoted

Signed-off-by: Jisheng Zhang <redacted>
---
 drivers/android/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig
index 832e885349b1..aca5dc30b97b 100644
--- a/drivers/android/Kconfig
+++ b/drivers/android/Kconfig

@@ -32,7 +32,7 @@ config ANDROID_BINDER_DEVICES
      therefore logically separated from the other devices.

 config ANDROID_BINDER_IPC_32BIT
-   bool
+   bool "Use old (Android 4.4 and earlier) 32-bit binder API"
    depends on !64BIT && ANDROID_BINDER_IPC  

You don't actually change the depends line :(

Please fix up, and test it, and then resend.  

IHOM, the dependency is correct: 64bit platforms don't support
ANDROID_BINDER_IPC_32BIT. What do you think?  

I think this indicates the commit message is unclear.

Part of it is that the config is inverted from the description. The
patch doesn't enable the 32bit legacy binder ABI on 32bit systems, it
just allows the option to be unselected, so that the 64bit ABI will be
used on 32bit systems.

Conceptually I don't have an objection to the change (though maybe try
to rework the commit message), but I don't have anything to actually
test it on right now, so I'm hesitant to ack it.  

It might also be good to add some detail as to the motivation for this
change? What benefit does it bring to 32bit platforms to use the newer
64bit ABI?  

It allows running the same 32-bit userspace build whether the kernel
is 64-bit or 32-bit.

Oh, yes, this is a good "motivation" which can be added into the commit msg.

thanks for the inspiration.