Re: [PATCH v5 02/10] powerpc/powernv/idle: Restore AMR/UAMOR/AMOR after idle
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2019-03-20 13:02:31
Akshay Adiga [off-list ref] writes:
On Fri, Mar 08, 2019 at 12:16:11PM +1100, Michael Ellerman wrote:quoted
In order to implement KUAP (Kernel Userspace Access Protection) on Power9 we will be using the AMR, and therefore indirectly the UAMOR/AMOR. So save/restore these regs in the idle code. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> --- v5: Unchanged. v4: New. arch/powerpc/kernel/idle_book3s.S | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-)Opps.. i posted a comment on the v4. It would be good if we can make AMOR/UAMOR/AMR save-restore code power9 only.
Yes that would be a good optimisation. If you can send an incremental patch against this one I'll squash it in. If not I'll try and get it done at some point before merging. cheers