From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755450Ab3B1Oq1 (ORCPT ); Thu, 28 Feb 2013 09:46:27 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:41919 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754872Ab3B1OqX (ORCPT ); Thu, 28 Feb 2013 09:46:23 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Christian Borntraeger , Gleb Natapov , Luis Henriques Subject: [PATCH 016/139] s390/kvm: Fix store status for ACRS/FPRS Date: Thu, 28 Feb 2013 14:42:46 +0000 Message-Id: <1362062689-2567-17-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1362062689-2567-1-git-send-email-luis.henriques@canonical.com> References: <1362062689-2567-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.5.7.7 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Christian Borntraeger commit 15bc8d8457875f495c59d933b05770ba88d1eacb upstream. On store status we need to copy the current state of registers into a save area. Currently we might save stale versions: The sie state descriptor doesnt have fields for guest ACRS,FPRS, those registers are simply stored in the host registers. The host program must copy these away if needed. We do that in vcpu_put/load. If we now do a store status in KVM code between vcpu_put/load, the saved values are not up-to-date. Lets collect the ACRS/FPRS before saving them. This also fixes some strange problems with hotplug and virtio-ccw, since the low level machine check handler (on hotplug a machine check will happen) will revalidate all registers with the content of the save area. Signed-off-by: Christian Borntraeger Signed-off-by: Gleb Natapov Signed-off-by: Luis Henriques --- arch/s390/kvm/kvm-s390.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index cea9701..62b5053 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -752,6 +752,14 @@ int kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, unsigned long addr) } else prefix = 0; + /* + * The guest FPRS and ACRS are in the host FPRS/ACRS due to the lazy + * copying in vcpu load/put. Lets update our copies before we save + * it into the save area + */ + save_fp_regs(&vcpu->arch.guest_fpregs); + save_access_regs(vcpu->run->s.regs.acrs); + if (__guestcopy(vcpu, addr + offsetof(struct save_area, fp_regs), vcpu->arch.guest_fpregs.fprs, 128, prefix)) return -EFAULT; -- 1.8.1.2