Re: [PATCH v4.4 backport 06/16] powerpc/64: Add macros for annotating the destination of rfid/hrfid
From: Greg KH <hidden>
Date: 2018-02-04 11:29:52
Also in:
stable
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