From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754856Ab0LGQPq (ORCPT ); Tue, 7 Dec 2010 11:15:46 -0500 Received: from va3ehsobe001.messaging.microsoft.com ([216.32.180.11]:58492 "EHLO VA3EHSOBE008.bigfish.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753996Ab0LGQPm (ORCPT ); Tue, 7 Dec 2010 11:15:42 -0500 X-SpamScore: -9 X-BigFish: VPS-9(zzbb2cK14ffOzz1202hzz8275bhz32i668h61h) X-Spam-TCS-SCL: 0:0 X-Forefront-Antispam-Report: KIP:(null);UIP:(null);IPVD:NLI;H:ausb3twp01.amd.com;RD:none;EFVD:NLI X-WSS-ID: 0LD2FTY-01-XMV-02 X-M-MSG: From: Joerg Roedel To: Avi Kivity , Marcelo Tosatti CC: , , Joerg Roedel Subject: [PATCH 2/2] KVM: SVM: Add xsetbv intercept Date: Tue, 7 Dec 2010 17:15:06 +0100 Message-ID: <1291738506-16278-2-git-send-email-joerg.roedel@amd.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <20101207161211.GD13125@amd.com> References: <20101207161211.GD13125@amd.com> MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch implements the xsetbv intercept to the AMD part of KVM. This makes AVX usable in a save way for the guest on AVX capable AMD hardware. The patch is tested by using AVX in the guest and host in parallel and checking for data corruption. I also used the KVM xsave unit-tests and they all pass. Signed-off-by: Joerg Roedel --- arch/x86/include/asm/svm.h | 2 ++ arch/x86/kvm/svm.c | 20 ++++++++++++++++---- 2 files changed, 18 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/svm.h b/arch/x86/include/asm/svm.h index 11dbca7..7f3a304 100644 --- a/arch/x86/include/asm/svm.h +++ b/arch/x86/include/asm/svm.h @@ -47,6 +47,7 @@ enum { INTERCEPT_MONITOR, INTERCEPT_MWAIT, INTERCEPT_MWAIT_COND, + INTERCEPT_XSETBV, }; @@ -326,6 +327,7 @@ struct __attribute__ ((__packed__)) vmcb { #define SVM_EXIT_MONITOR 0x08a #define SVM_EXIT_MWAIT 0x08b #define SVM_EXIT_MWAIT_COND 0x08c +#define SVM_EXIT_XSETBV 0x08d #define SVM_EXIT_NPF 0x400 #define SVM_EXIT_ERR -1 diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 8aeda9f..4a5e584 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -904,6 +904,7 @@ static void init_vmcb(struct vcpu_svm *svm) set_intercept(svm, INTERCEPT_WBINVD); set_intercept(svm, INTERCEPT_MONITOR); set_intercept(svm, INTERCEPT_MWAIT); + set_intercept(svm, INTERCEPT_XSETBV); control->iopm_base_pa = iopm_base; control->msrpm_base_pa = __pa(svm->msrpm); @@ -2494,6 +2495,19 @@ static int skinit_interception(struct vcpu_svm *svm) return 1; } +static int xsetbv_interception(struct vcpu_svm *svm) +{ + u64 new_bv = kvm_read_edx_eax(&svm->vcpu); + u32 index = kvm_register_read(&svm->vcpu, VCPU_REGS_RCX); + + if (kvm_set_xcr(&svm->vcpu, index, new_bv) == 0) { + svm->next_rip = kvm_rip_read(&svm->vcpu) + 3; + skip_emulated_instruction(&svm->vcpu); + } + + return 1; +} + static int invalid_op_interception(struct vcpu_svm *svm) { kvm_queue_exception(&svm->vcpu, UD_VECTOR); @@ -2917,6 +2931,7 @@ static int (*svm_exit_handlers[])(struct vcpu_svm *svm) = { [SVM_EXIT_WBINVD] = emulate_on_interception, [SVM_EXIT_MONITOR] = invalid_op_interception, [SVM_EXIT_MWAIT] = invalid_op_interception, + [SVM_EXIT_XSETBV] = xsetbv_interception, [SVM_EXIT_NPF] = pf_interception, }; @@ -3556,10 +3571,6 @@ static void svm_cpuid_update(struct kvm_vcpu *vcpu) static void svm_set_supported_cpuid(u32 func, struct kvm_cpuid_entry2 *entry) { switch (func) { - case 0x00000001: - /* Mask out xsave bit as long as it is not supported by SVM */ - entry->ecx &= ~(bit(X86_FEATURE_XSAVE)); - break; case 0x80000001: if (nested) entry->ecx |= (1 << 2); /* Set SVM bit */ @@ -3633,6 +3644,7 @@ static const struct trace_print_flags svm_exit_reasons_str[] = { { SVM_EXIT_WBINVD, "wbinvd" }, { SVM_EXIT_MONITOR, "monitor" }, { SVM_EXIT_MWAIT, "mwait" }, + { SVM_EXIT_XSETBV, "xsetbv" }, { SVM_EXIT_NPF, "npf" }, { -1, NULL } }; -- 1.7.1