From patchwork Fri Sep 28 05:29:11 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Mackerras X-Patchwork-Id: 187718 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 3ACB32C00D1 for ; Fri, 28 Sep 2012 15:29:00 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750981Ab2I1F27 (ORCPT ); Fri, 28 Sep 2012 01:28:59 -0400 Received: from ozlabs.org ([203.10.76.45]:43607 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750900Ab2I1F26 (ORCPT ); Fri, 28 Sep 2012 01:28:58 -0400 Received: by ozlabs.org (Postfix, from userid 1003) id 34B3C2C00DD; Fri, 28 Sep 2012 15:28:56 +1000 (EST) Date: Fri, 28 Sep 2012 15:29:11 +1000 From: Paul Mackerras To: Alexander Graf Cc: kvm-ppc@vger.kernel.org, kvm@vger.kernel.org Subject: [PATCH] KVM: PPC: Book3S HV: Allow DTL to be unregistered through KVM_SET_ONE_REG interface Message-ID: <20120928052911.GA4852@bloggs.ozlabs.ibm.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) Sender: kvm-ppc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm-ppc@vger.kernel.org From 0912ff6f7d95aa559af75ba69aa7f661357f5dce Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Fri, 28 Sep 2012 15:26:07 +1000 Subject: [PATCH] KVM: PPC: Book3S HV: Allow DTL to be set to address 0, length 0 Recently-added code to allow the dispatch trace log buffer address to be set with the KVM_SET_ONE_REG interface includes a check on the length to make sure the buffer is at least one entry long. This is appropriate when registering a buffer, but the interface also allows for any existing buffer to be unregistered by specifying a zero address. In this case the length check is not appropriate, so this makes the check conditional on the address being non-zero. Signed-off-by: Paul Mackerras --- arch/powerpc/kvm/book3s_hv.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index 350b038..1eda13d 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -854,9 +854,8 @@ int kvmppc_set_one_reg(struct kvm_vcpu *vcpu, u64 id, union kvmppc_one_reg *val) addr = val->vpaval.addr; len = val->vpaval.length; r = -EINVAL; - if (len < sizeof(struct dtl_entry)) - break; - if (addr && !vcpu->arch.vpa.next_gpa) + if (addr && (len < sizeof(struct dtl_entry) || + !vcpu->arch.vpa.next_gpa)) break; len -= len % sizeof(struct dtl_entry); r = set_vpa(vcpu, &vcpu->arch.dtl, addr, len);