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Date: Fri, 18 Sep 2015 11:27:32 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>, ebiederm@xmission.com,
        Al Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Kostya Serebryany <kcc@google.com>,
        Andrey Konovalov <andreyknvl@google.com>,
        Alexander Potapenko <glider@google.com>,
        Hans Boehm <hboehm@google.com>, james.hogan@imgtec.com
Subject: Re: [PATCH] kernel: fix data race in put_pid
Message-ID: <20150918092732.GD11639@twins.programming.kicks-ass.net>
References: <1442496268-47803-1-git-send-email-dvyukov@google.com>
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On Fri, Sep 18, 2015 at 10:57:32AM +0200, Peter Zijlstra wrote:
> diff --git a/arch/metag/include/asm/atomic_lnkget.h b/arch/metag/include/asm/atomic_lnkget.h
> index 21c4c268b86c..1bd21c933435 100644
> --- a/arch/metag/include/asm/atomic_lnkget.h
> +++ b/arch/metag/include/asm/atomic_lnkget.h
> @@ -3,7 +3,8 @@
>  
>  #define ATOMIC_INIT(i)	{ (i) }
>  
> -#define atomic_set(v, i)		((v)->counter = (i))
> +/* XXX: should be LNKSETD ? */
> +#define atomic_set(v, i)		WRITE_ONCE((v)->counter, (i))
>  
>  #include <linux/compiler.h>
>  

James?