From patchwork Mon Jun 8 08:32:19 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 28595 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n588WRU5002150 for ; Mon, 8 Jun 2009 08:32:27 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753939AbZFHIcU (ORCPT ); Mon, 8 Jun 2009 04:32:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753775AbZFHIcU (ORCPT ); Mon, 8 Jun 2009 04:32:20 -0400 Received: from mga02.intel.com ([134.134.136.20]:47189 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753569AbZFHIcS (ORCPT ); Mon, 8 Jun 2009 04:32:18 -0400 Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP; 08 Jun 2009 01:23:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.41,323,1241420400"; d="scan'208";a="419738806" Received: from yhuang-dev.sh.intel.com (HELO [10.239.13.137]) ([10.239.13.137]) by orsmga002.jf.intel.com with ESMTP; 08 Jun 2009 01:39:44 -0700 Subject: [PATCH -v3] KVM: Add VT-x machine check support From: Huang Ying To: "avi@redhat.com" , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , Andi Kleen Date: Mon, 08 Jun 2009 16:32:19 +0800 Message-Id: <1244449939.8361.591.camel@yhuang-dev.sh.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1.1 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Andi Kleen VT-x needs an explicit MC vector intercept to handle machine checks in the hyper visor. It also has a special option to catch machine checks that happen during VT entry. Do these interceptions and forward them to the Linux machine check handler. Make it always look like user space is interrupted because the machine check handler treats kernel/user space differently. Thanks to Jiang Yunhong for help and testing. v3: Rebased on kvm.git v2: Handle machine checks still in interrupt off context to avoid problems on preemptible kernels. Signed-off-by: Andi Kleen Signed-off-by: Huang Ying --- arch/x86/include/asm/kvm_host.h | 2 + arch/x86/include/asm/vmx.h | 1 arch/x86/kernel/cpu/mcheck/mce_64.c | 1 arch/x86/kvm/vmx.c | 41 +++++++++++++++++++++++++++++++++--- 4 files changed, 42 insertions(+), 3 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- a/arch/x86/include/asm/vmx.h +++ b/arch/x86/include/asm/vmx.h @@ -247,6 +247,7 @@ enum vmcs_field { #define EXIT_REASON_MSR_READ 31 #define EXIT_REASON_MSR_WRITE 32 #define EXIT_REASON_MWAIT_INSTRUCTION 36 +#define EXIT_REASON_MCE_DURING_VMENTRY 41 #define EXIT_REASON_TPR_BELOW_THRESHOLD 43 #define EXIT_REASON_APIC_ACCESS 44 #define EXIT_REASON_EPT_VIOLATION 48 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -32,6 +32,7 @@ #include #include #include +#include #define __ex(x) __kvm_handle_fault_on_reboot(x) @@ -487,7 +488,7 @@ static void update_exception_bitmap(stru { u32 eb; - eb = (1u << PF_VECTOR) | (1u << UD_VECTOR); + eb = (1u << PF_VECTOR) | (1u << UD_VECTOR) | (1u << MC_VECTOR); if (!vcpu->fpu_active) eb |= 1u << NM_VECTOR; if (vcpu->guest_debug & KVM_GUESTDBG_ENABLE) { @@ -2605,6 +2606,29 @@ static int handle_rmode_exception(struct return 0; } +/* + * Trigger machine check on the host. We assume all the MSRs are already set up + * by the CPU and that we still run on the same CPU as the MCE occurred on. + * We pass a fake environment to the machine check handler because we want + * the guest to be always treated like user space, no matter what context + * it used internally. + */ +static void kvm_machine_check(void) +{ + struct pt_regs regs = { + .cs = 3, /* Fake ring 3 no matter what the guest ran on */ + .flags = X86_EFLAGS_IF, + }; + + do_machine_check(®s, 0); +} + +static int handle_machine_check(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) +{ + /* already handled by vcpu_run */ + return 1; +} + static int handle_exception(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { struct vcpu_vmx *vmx = to_vmx(vcpu); @@ -2616,6 +2640,10 @@ static int handle_exception(struct kvm_v vect_info = vmx->idt_vectoring_info; intr_info = vmcs_read32(VM_EXIT_INTR_INFO); + ex_no = intr_info & INTR_INFO_VECTOR_MASK; + if (ex_no == MC_VECTOR) + return handle_machine_check(vcpu, kvm_run); + if ((vect_info & VECTORING_INFO_VALID_MASK) && !is_page_fault(intr_info)) printk(KERN_ERR "%s: unexpected, vectoring info 0x%x " @@ -2662,7 +2690,6 @@ static int handle_exception(struct kvm_v return 1; } - ex_no = intr_info & INTR_INFO_VECTOR_MASK; switch (ex_no) { case DB_VECTOR: dr6 = vmcs_readl(EXIT_QUALIFICATION); @@ -3189,6 +3216,7 @@ static int (*kvm_vmx_exit_handlers[])(st [EXIT_REASON_WBINVD] = handle_wbinvd, [EXIT_REASON_TASK_SWITCH] = handle_task_switch, [EXIT_REASON_EPT_VIOLATION] = handle_ept_violation, + [EXIT_REASON_MCE_DURING_VMENTRY] = handle_machine_check, }; static const int kvm_vmx_max_exit_handlers = @@ -3200,7 +3228,7 @@ static const int kvm_vmx_max_exit_handle */ static int vmx_handle_exit(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu) { - u32 exit_reason = vmcs_read32(VM_EXIT_REASON); + u32 exit_reason = vcpu->arch.exit_reason; struct vcpu_vmx *vmx = to_vmx(vcpu); u32 vectoring_info = vmx->idt_vectoring_info; @@ -3284,6 +3312,13 @@ static void vmx_complete_interrupts(stru exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO); + vmx->vcpu.arch.exit_reason = vmcs_read32(VM_EXIT_REASON); + + /* Handle machine checks before interrupts are enabled */ + if ((vmx->vcpu.arch.exit_reason == EXIT_REASON_MCE_DURING_VMENTRY) || + (exit_intr_info & INTR_INFO_VECTOR_MASK) == MC_VECTOR) + kvm_machine_check(); + /* We need to handle NMIs before interrupts are enabled */ if ((exit_intr_info & INTR_INFO_INTR_TYPE_MASK) == INTR_TYPE_NMI_INTR && (exit_intr_info & INTR_INFO_VALID_MASK)) { --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -382,6 +382,8 @@ struct kvm_vcpu_arch { u64 mcg_status; u64 mcg_ctl; u64 *mce_banks; + + u32 exit_reason; }; struct kvm_mem_alias { --- a/arch/x86/kernel/cpu/mcheck/mce_64.c +++ b/arch/x86/kernel/cpu/mcheck/mce_64.c @@ -420,6 +420,7 @@ void do_machine_check(struct pt_regs * r out2: atomic_dec(&mce_entry); } +EXPORT_SYMBOL_GPL(do_machine_check); #ifdef CONFIG_X86_MCE_INTEL /***