From patchwork Thu Oct 31 21:18:04 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Graf X-Patchwork-Id: 287654 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 6D75B2C03EE for ; Fri, 1 Nov 2013 08:20:55 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755712Ab3JaVUq (ORCPT ); Thu, 31 Oct 2013 17:20:46 -0400 Received: from cantor2.suse.de ([195.135.220.15]:54384 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755464Ab3JaVSo (ORCPT ); Thu, 31 Oct 2013 17:18:44 -0400 Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id D0824A60D1; Thu, 31 Oct 2013 22:18:40 +0100 (CET) From: Alexander Graf To: "kvm@vger.kernel.org mailing list" Cc: kvm-ppc@vger.kernel.org, Gleb Natapov , Paolo Bonzini , Paul Mackerras Subject: [PULL 19/51] KVM: PPC: Book3S PR: Correct errors in H_ENTER implementation Date: Thu, 31 Oct 2013 22:18:04 +0100 Message-Id: <1383254316-11243-20-git-send-email-agraf@suse.de> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1383254316-11243-1-git-send-email-agraf@suse.de> References: <1383254316-11243-1-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 From: Paul Mackerras The implementation of H_ENTER in PR KVM has some errors: * With H_EXACT not set, if the HPTEG is full, we return H_PTEG_FULL as the return value of kvmppc_h_pr_enter, but the caller is expecting one of the EMULATE_* values. The H_PTEG_FULL needs to go in the guest's R3 instead. * With H_EXACT set, if the selected HPTE is already valid, the H_ENTER call should return a H_PTEG_FULL error. This fixes these errors and also makes it write only the selected HPTE, not the whole group, since only the selected HPTE has been modified. This also micro-optimizes the calculations involving pte_index and i. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf --- arch/powerpc/kvm/book3s_pr_papr.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) diff --git a/arch/powerpc/kvm/book3s_pr_papr.c b/arch/powerpc/kvm/book3s_pr_papr.c index da0e0bc..38f1899 100644 --- a/arch/powerpc/kvm/book3s_pr_papr.c +++ b/arch/powerpc/kvm/book3s_pr_papr.c @@ -21,6 +21,8 @@ #include #include +#define HPTE_SIZE 16 /* bytes per HPT entry */ + static unsigned long get_pteg_addr(struct kvm_vcpu *vcpu, long pte_index) { struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu); @@ -40,32 +42,39 @@ static int kvmppc_h_pr_enter(struct kvm_vcpu *vcpu) long pte_index = kvmppc_get_gpr(vcpu, 5); unsigned long pteg[2 * 8]; unsigned long pteg_addr, i, *hpte; + long int ret; + i = pte_index & 7; pte_index &= ~7UL; pteg_addr = get_pteg_addr(vcpu, pte_index); copy_from_user(pteg, (void __user *)pteg_addr, sizeof(pteg)); hpte = pteg; + ret = H_PTEG_FULL; if (likely((flags & H_EXACT) == 0)) { - pte_index &= ~7UL; for (i = 0; ; ++i) { if (i == 8) - return H_PTEG_FULL; + goto done; if ((*hpte & HPTE_V_VALID) == 0) break; hpte += 2; } } else { - i = kvmppc_get_gpr(vcpu, 5) & 7UL; hpte += i * 2; + if (*hpte & HPTE_V_VALID) + goto done; } hpte[0] = kvmppc_get_gpr(vcpu, 6); hpte[1] = kvmppc_get_gpr(vcpu, 7); - copy_to_user((void __user *)pteg_addr, pteg, sizeof(pteg)); - kvmppc_set_gpr(vcpu, 3, H_SUCCESS); + pteg_addr += i * HPTE_SIZE; + copy_to_user((void __user *)pteg_addr, hpte, HPTE_SIZE); kvmppc_set_gpr(vcpu, 4, pte_index | i); + ret = H_SUCCESS; + + done: + kvmppc_set_gpr(vcpu, 3, ret); return EMULATE_DONE; }