Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751578AbdGYKrA (ORCPT ); Tue, 25 Jul 2017 06:47:00 -0400 Received: from ozlabs.org ([103.22.144.67]:48323 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750968AbdGYKqX (ORCPT ); Tue, 25 Jul 2017 06:46:23 -0400 From: Michael Ellerman To: Nicholas Piggin , Gautham R Shenoy Cc: Michael Neuling , Vaidyanathan Srinivasan , Shilpasri G Bhat , Akshay Adiga , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] powernv/powerpc: Clear PECE1 in LPCR via stop-api only on Hotplug In-Reply-To: <20170719152032.7724085f@roar.ozlabs.ibm.com> References: <20170719121412.1d89857c@roar.ozlabs.ibm.com> <20170719050459.GA30836@in.ibm.com> <20170719152032.7724085f@roar.ozlabs.ibm.com> User-Agent: Notmuch/0.21 (https://notmuchmail.org) Date: Tue, 25 Jul 2017 20:46:19 +1000 Message-ID: <8760eg7q10.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 499 Lines: 14 Nicholas Piggin writes: ... > I wonder if we should think about a more structured kernel API for > modifying these kind of system registers so we always have the > up-to-date values stored in memory. Many of them do need to be > restored after sleep, but they don't need to be saved per-thread > or saved every time we go to sleep. Yes that's on my mental TODO. Paul and I have talked about it in the past for KVM. I'll write it down sometime so we at least remember :D chers