Subject: Re: linux-next: build failure after merge of the rcu tree

From: "Paul E. McKenney" <[email-masked]>
Date: Mon, 28 Aug 2017 10:50:51 -0700

On Mon, Aug 28, 2017 at 02:25:48PM +1000, Stephen Rothwell wrote:
> Hi Paul,
> 
> After merging the rcu tree, today's linux-next build (arm
> multi_v7_defconfig) failed like this:
> 
> In file included from arch/arm/kernel/asm-offsets.c:14:0:
> include/linux/sched.h: In function 'membarrier_sched_out':
> include/linux/sched.h:1680:3: error: implicit declaration of function 'sync_core' [-Werror=implicit-function-declaration]
>    sync_core();
>    ^
> 
> Caused by commit
> 
>   0d6eb99818da ("membarrier: Provide register sync core cmd")
> 
> I have used the rcu tree from next-20170825 for today.

I have dropped this, and will likely re-add with the facility provided
or with an ARCH_ kconfig option.

Sorry for the hassle!

							Thanx, Paul