From patchwork Fri Feb 24 14:26:23 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Graf X-Patchwork-Id: 142864 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 76B61B6FF8 for ; Sat, 25 Feb 2012 01:27:17 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756104Ab2BXO1G (ORCPT ); Fri, 24 Feb 2012 09:27:06 -0500 Received: from cantor2.suse.de ([195.135.220.15]:42499 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755489Ab2BXO0i (ORCPT ); Fri, 24 Feb 2012 09:26:38 -0500 Received: from relay2.suse.de (unknown [195.135.220.254]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx2.suse.de (Postfix) with ESMTP id EF72093583; Fri, 24 Feb 2012 15:26:32 +0100 (CET) From: Alexander Graf To: kvm-ppc@vger.kernel.org Cc: kvm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Scott Wood Subject: [PATCH 29/37] KVM: PPC: bookehv: disable MAS register updates early Date: Fri, 24 Feb 2012 15:26:23 +0100 Message-Id: <1330093591-19523-30-git-send-email-agraf@suse.de> X-Mailer: git-send-email 1.7.3.4 In-Reply-To: <1330093591-19523-1-git-send-email-agraf@suse.de> References: <1330093591-19523-1-git-send-email-agraf@suse.de> Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org We need to make sure that no MAS updates happen automatically while we have the guest MAS registers loaded. So move the disabling code a bit higher up so that it covers the full time we have guest values in MAS registers. The race this patch fixes should never occur, but it makes the code a bit more logical to do it this way around. Signed-off-by: Alexander Graf --- arch/powerpc/kvm/bookehv_interrupts.S | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kvm/bookehv_interrupts.S b/arch/powerpc/kvm/bookehv_interrupts.S index 469bd3f..021d087 100644 --- a/arch/powerpc/kvm/bookehv_interrupts.S +++ b/arch/powerpc/kvm/bookehv_interrupts.S @@ -358,6 +358,7 @@ _GLOBAL(kvmppc_resume_host) mtspr SPRN_MAS4, r6 stw r5, VCPU_SHARED_MAS7_3+0(r11) mtspr SPRN_MAS6, r8 + /* Enable MAS register updates via exception */ mfspr r3, SPRN_EPCR rlwinm r3, r3, 0, ~SPRN_EPCR_DMIUH mtspr SPRN_EPCR, r3 @@ -515,6 +516,11 @@ lightweight_exit: mtspr SPRN_PID, r3 PPC_LL r11, VCPU_SHARED(r4) + /* Disable MAS register updates via exception */ + mfspr r3, SPRN_EPCR + oris r3, r3, SPRN_EPCR_DMIUH@h + mtspr SPRN_EPCR, r3 + isync /* Save host mas4 and mas6 and load guest MAS registers */ mfspr r3, SPRN_MAS4 stw r3, VCPU_HOST_MAS4(r4) @@ -538,10 +544,6 @@ lightweight_exit: lwz r5, VCPU_SHARED_MAS7_3+0(r11) mtspr SPRN_MAS6, r3 mtspr SPRN_MAS7, r5 - /* Disable MAS register updates via exception */ - mfspr r3, SPRN_EPCR - oris r3, r3, SPRN_EPCR_DMIUH@h - mtspr SPRN_EPCR, r3 /* * Host interrupt handlers may have clobbered these guest-readable