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Date: Tue, 16 Jan 2018 19:28:07 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
cc: Ingo Molnar <mingo@redhat.com>,
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Subject: Re: [PATCH for 4.16 07/10] x86: Introduce sync_core_before_usermode
 (v2)
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On Mon, 15 Jan 2018, Mathieu Desnoyers wrote:

> Introduce an architecture function that ensures the current CPU
> issues a core serializing instruction before returning to usermode.
> 
> This is needed for the membarrier "sync_core" command.
> 
> Architectures defining the sync_core_before_usermode() static inline
> need to select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>