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Date: Sun, 4 Feb 2018 11:53:55 +0100
From: Greg KH <greg@kroah.com>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org
Subject: Re: [PATCH v4.4 backport 06/16] powerpc/64: Add macros for
 annotating the destination of rfid/hrfid
Message-ID: <20180204105355.GE7519@kroah.com>
References: <20180204050010.13669-1-mpe@ellerman.id.au>
 <20180204050010.13669-7-mpe@ellerman.id.au>
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On Sun, Feb 04, 2018 at 04:00:00PM +1100, Michael Ellerman wrote:
> From: Nicholas Piggin <npiggin@gmail.com>
> 
> commit 50e51c13b3822d14ff6df4279423e4b7b2269bc3 upstream.
> 
> The rfid/hrfid ((Hypervisor) Return From Interrupt) instruction is
> used for switching from the kernel to userspace, and from the
> hypervisor to the guest kernel. However it can and is also used for
> other transitions, eg. from real mode kernel code to virtual mode
> kernel code, and it's not always clear from the code what the
> destination context is.
> 
> To make it clearer when reading the code, add macros which encode the
> expected destination context.
> 
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Also applied to 4.9.y, thanks.

greg k-h