From patchwork Thu May 11 06:15:22 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mahesh J Salgaonkar X-Patchwork-Id: 9720993 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 946BE6031B for ; Thu, 11 May 2017 06:16:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8CEC22865A for ; Thu, 11 May 2017 06:16:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 81BFD28669; Thu, 11 May 2017 06:16:24 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6ABFC2865A for ; Thu, 11 May 2017 06:16:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753446AbdEKGQV (ORCPT ); Thu, 11 May 2017 02:16:21 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:49549 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752639AbdEKGQU (ORCPT ); Thu, 11 May 2017 02:16:20 -0400 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v4B69Qa9062576 for ; Thu, 11 May 2017 02:16:20 -0400 Received: from e23smtp06.au.ibm.com (e23smtp06.au.ibm.com [202.81.31.148]) by mx0a-001b2d01.pphosted.com with ESMTP id 2ac1y13sm7-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 11 May 2017 02:16:19 -0400 Received: from localhost by e23smtp06.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 11 May 2017 16:16:14 +1000 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay09.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v4B6G6fC28639394; Thu, 11 May 2017 16:16:14 +1000 Received: from d23av03.au.ibm.com (localhost [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v4B6FYXo014150; Thu, 11 May 2017 16:15:35 +1000 Received: from jupiter.in.ibm.com ([9.202.49.117]) by d23av03.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id v4B6FWld013269; Thu, 11 May 2017 16:15:32 +1000 Subject: [PATCH v9 1/3] KVM: PPC: Add new capability to control MCE behaviour From: Mahesh J Salgaonkar To: gleb@kernel.org, agraf@suse.de, kvm-ppc@vger.kernel.org, linuxppc-dev , Paul Mackerras , pbonzini@redhat.com Cc: Michael Ellerman , kvm@vger.kernel.org, david@gibson.dropbear.id.au Date: Thu, 11 May 2017 11:45:22 +0530 In-Reply-To: <149448323691.12206.11861424815113458031.stgit@jupiter.in.ibm.com> References: <149448323691.12206.11861424815113458031.stgit@jupiter.in.ibm.com> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-TM-AS-MML: disable x-cbid: 17051106-0040-0000-0000-00000316D6EF X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17051106-0041-0000-0000-00000C8F5065 Message-Id: <149448332189.12206.5811614133100561669.stgit@jupiter.in.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-05-11_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1705110039 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Aravinda Prasad This patch introduces a new KVM capability to control how KVM behaves on machine check exception (MCE). Without this capability, KVM redirects machine check exceptions to guest's 0x200 vector, if the address in error belongs to the guest. With this capability KVM causes a guest exit with NMI exit reason. The new capability is required to avoid problems if a new kernel/KVM is used with an old QEMU for guests that don't issue "ibm,nmi-register". As old QEMU does not understand the NMI exit type, it treats it as a fatal error. However, the guest could have handled the machine check error if the exception was delivered to guest's 0x200 interrupt vector instead of NMI exit in case of old QEMU. Signed-off-by: Aravinda Prasad Reviewed-by: David Gibson Signed-off-by: Mahesh Salgaonkar --- Documentation/virtual/kvm/api.txt | 11 +++++++++++ arch/powerpc/include/asm/kvm_host.h | 1 + arch/powerpc/kernel/asm-offsets.c | 1 + arch/powerpc/kvm/powerpc.c | 9 +++++++++ include/uapi/linux/kvm.h | 1 + 5 files changed, 23 insertions(+) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 4029943..3cdf203 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -3996,6 +3996,17 @@ Parameters: none Allow use of adapter-interruption suppression. Returns: 0 on success; -EBUSY if a VCPU has already been created. +7.11 KVM_CAP_PPC_FWNMI + +Architectures: ppc +Parameters: none + +With this capability a machine check exception in the guest address +space will cause KVM to exit the guest with NMI exit reason. This +enables QEMU to build error log and branch to guest kernel registered +machine check handling routine. Without this capability KVM will +branch to guests' 0x200 interrupt vector. + 8. Other capabilities. ---------------------- diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 77c6082..fad522d 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -284,6 +284,7 @@ struct kvm_arch { struct dentry *debugfs_dir; struct dentry *htab_dentry; struct kvm_resize_hpt *resize_hpt; /* protected by kvm->lock */ + u8 fwnmi_enabled; #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */ #ifdef CONFIG_KVM_BOOK3S_PR_POSSIBLE struct mutex hpt_mutex; diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c index 439c257..6f742af 100644 --- a/arch/powerpc/kernel/asm-offsets.c +++ b/arch/powerpc/kernel/asm-offsets.c @@ -485,6 +485,7 @@ int main(void) OFFSET(KVM_ENABLED_HCALLS, kvm, arch.enabled_hcalls); OFFSET(KVM_VRMA_SLB_V, kvm, arch.vrma_slb_v); OFFSET(KVM_RADIX, kvm, arch.radix); + OFFSET(KVM_FWNMI, kvm, arch.fwnmi_enabled); OFFSET(VCPU_DSISR, kvm_vcpu, arch.shregs.dsisr); OFFSET(VCPU_DAR, kvm_vcpu, arch.shregs.dar); OFFSET(VCPU_VPA, kvm_vcpu, arch.vpa.pinned_addr); diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 1ee22a9..3400477 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -616,6 +616,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) /* Disable this on POWER9 until code handles new HPTE format */ r = !!hv_enabled && !cpu_has_feature(CPU_FTR_ARCH_300); break; + case KVM_CAP_PPC_FWNMI: + r = 1; + break; #endif case KVM_CAP_PPC_HTM: r = cpu_has_feature(CPU_FTR_TM_COMP) && @@ -1529,6 +1532,12 @@ static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, break; } #endif /* CONFIG_KVM_XICS */ +#ifdef CONFIG_PPC_BOOK3S_64 + case KVM_CAP_PPC_FWNMI: + r = 0; + vcpu->kvm->arch.fwnmi_enabled = true; + break; +#endif /* CONFIG_PPC_BOOK3S_64 */ default: r = -EINVAL; break; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index 577429a..89bc145 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -895,6 +895,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_SPAPR_TCE_VFIO 142 #define KVM_CAP_X86_GUEST_MWAIT 143 #define KVM_CAP_ARM_USER_IRQ 144 +#define KVM_CAP_PPC_FWNMI 145 #ifdef KVM_CAP_IRQ_ROUTING