Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753095AbdHQL7N (ORCPT ); Thu, 17 Aug 2017 07:59:13 -0400 Received: from mga04.intel.com ([192.55.52.120]:25845 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752570AbdHQL7I (ORCPT ); Thu, 17 Aug 2017 07:59:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.41,387,1498546800"; d="scan'208";a="301350160" From: Yu Zhang To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, pbonzini@redhat.com, rkrcmar@redhat.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, xiaoguangrong@tencent.com, joro@8bytes.org Subject: [PATCH v2 1/5] KVM: x86: Add return value to kvm_cpuid(). Date: Fri, 18 Aug 2017 03:52:34 +0800 Message-Id: <1502999558-2517-2-git-send-email-yu.c.zhang@linux.intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1502999558-2517-1-git-send-email-yu.c.zhang@linux.intel.com> References: <1502999558-2517-1-git-send-email-yu.c.zhang@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8407 Lines: 243 Return false in kvm_cpuid() when it fails to find the cpuid entry. Also, this routine(and its caller) is optimized with a new argument - check_limit, so that the check_cpuid_limit() fall back can be avoided. Signed-off-by: Yu Zhang --- arch/x86/include/asm/kvm_emulate.h | 4 ++-- arch/x86/kvm/cpuid.c | 18 ++++++++++++++---- arch/x86/kvm/cpuid.h | 9 ++++++++- arch/x86/kvm/emulate.c | 17 ++++++++++------- arch/x86/kvm/svm.c | 2 +- arch/x86/kvm/trace.h | 11 +++++++---- arch/x86/kvm/x86.c | 6 +++--- 7 files changed, 45 insertions(+), 22 deletions(-) diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h index fde36f1..0e51a07 100644 --- a/arch/x86/include/asm/kvm_emulate.h +++ b/arch/x86/include/asm/kvm_emulate.h @@ -219,8 +219,8 @@ struct x86_emulate_ops { struct x86_instruction_info *info, enum x86_intercept_stage stage); - void (*get_cpuid)(struct x86_emulate_ctxt *ctxt, - u32 *eax, u32 *ebx, u32 *ecx, u32 *edx); + bool (*get_cpuid)(struct x86_emulate_ctxt *ctxt, u32 *eax, u32 *ebx, + u32 *ecx, u32 *edx, int check_limit); void (*set_nmi_mask)(struct x86_emulate_ctxt *ctxt, bool masked); unsigned (*get_hflags)(struct x86_emulate_ctxt *ctxt); diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 59ca2ee..989ba4e 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -853,15 +853,22 @@ static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu, return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index); } -void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) +bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, + u32 *ecx, u32 *edx, int check_limit) { u32 function = *eax, index = *ecx; struct kvm_cpuid_entry2 *best; + bool entry_found = true; best = kvm_find_cpuid_entry(vcpu, function, index); - if (!best) + if (!best) { + entry_found = false; + if (!check_limit) + goto out; + best = check_cpuid_limit(vcpu, function, index); + } if (best) { *eax = best->eax; @@ -870,7 +877,10 @@ void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) *edx = best->edx; } else *eax = *ebx = *ecx = *edx = 0; - trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx); + +out: + trace_kvm_cpuid(function, *eax, *ebx, *ecx, *edx, entry_found); + return entry_found; } EXPORT_SYMBOL_GPL(kvm_cpuid); @@ -883,7 +893,7 @@ int kvm_emulate_cpuid(struct kvm_vcpu *vcpu) eax = kvm_register_read(vcpu, VCPU_REGS_RAX); ecx = kvm_register_read(vcpu, VCPU_REGS_RCX); - kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx); + kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx, CHECK_LIMIT); kvm_register_write(vcpu, VCPU_REGS_RAX, eax); kvm_register_write(vcpu, VCPU_REGS_RBX, ebx); kvm_register_write(vcpu, VCPU_REGS_RCX, ecx); diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index ac15193..3e759cf 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -21,7 +21,14 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu, int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid, struct kvm_cpuid_entry2 __user *entries); -void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx); + +enum { + NO_CHECK_LIMIT = 0, + CHECK_LIMIT = 1, +}; + +bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, + u32 *ecx, u32 *edx, int check_limit); int cpuid_query_maxphyaddr(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index fb00559..46daa37 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -28,6 +28,7 @@ #include "x86.h" #include "tss.h" +#include "cpuid.h" /* * Operand types @@ -2333,8 +2334,10 @@ static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt) eax = 0x80000001; ecx = 0; - ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); - return edx & bit(X86_FEATURE_LM); + if (ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, NO_CHECK_LIMIT)) + return edx & bit(X86_FEATURE_LM); + else + return 0; } #define GET_SMSTATE(type, smbase, offset) \ @@ -2636,7 +2639,7 @@ static bool vendor_intel(struct x86_emulate_ctxt *ctxt) u32 eax, ebx, ecx, edx; eax = ecx = 0; - ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, NO_CHECK_LIMIT); return ebx == X86EMUL_CPUID_VENDOR_GenuineIntel_ebx && ecx == X86EMUL_CPUID_VENDOR_GenuineIntel_ecx && edx == X86EMUL_CPUID_VENDOR_GenuineIntel_edx; @@ -2656,7 +2659,7 @@ static bool em_syscall_is_enabled(struct x86_emulate_ctxt *ctxt) eax = 0x00000000; ecx = 0x00000000; - ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, NO_CHECK_LIMIT); /* * Intel ("GenuineIntel") * remark: Intel CPUs only support "syscall" in 64bit @@ -3551,7 +3554,7 @@ static int em_movbe(struct x86_emulate_ctxt *ctxt) /* * Check MOVBE is set in the guest-visible CPUID leaf. */ - ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, CHECK_LIMIT); if (!(ecx & FFL(MOVBE))) return emulate_ud(ctxt); @@ -3865,7 +3868,7 @@ static int em_cpuid(struct x86_emulate_ctxt *ctxt) eax = reg_read(ctxt, VCPU_REGS_RAX); ecx = reg_read(ctxt, VCPU_REGS_RCX); - ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, CHECK_LIMIT); *reg_write(ctxt, VCPU_REGS_RAX) = eax; *reg_write(ctxt, VCPU_REGS_RBX) = ebx; *reg_write(ctxt, VCPU_REGS_RCX) = ecx; @@ -3924,7 +3927,7 @@ static int check_fxsr(struct x86_emulate_ctxt *ctxt) { u32 eax = 1, ebx, ecx = 0, edx; - ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx); + ctxt->ops->get_cpuid(ctxt, &eax, &ebx, &ecx, &edx, CHECK_LIMIT); if (!(edx & FFL(FXSR))) return emulate_ud(ctxt); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 1fa9ee5..9def4a8 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -1580,7 +1580,7 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) } init_vmcb(svm); - kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy); + kvm_cpuid(vcpu, &eax, &dummy, &dummy, &dummy, CHECK_LIMIT); kvm_register_write(vcpu, VCPU_REGS_RDX, eax); if (kvm_vcpu_apicv_active(vcpu) && !init_event) diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h index 0a6cc67..8a202c4 100644 --- a/arch/x86/kvm/trace.h +++ b/arch/x86/kvm/trace.h @@ -151,8 +151,8 @@ TRACE_EVENT(kvm_fast_mmio, */ TRACE_EVENT(kvm_cpuid, TP_PROTO(unsigned int function, unsigned long rax, unsigned long rbx, - unsigned long rcx, unsigned long rdx), - TP_ARGS(function, rax, rbx, rcx, rdx), + unsigned long rcx, unsigned long rdx, bool found), + TP_ARGS(function, rax, rbx, rcx, rdx, found), TP_STRUCT__entry( __field( unsigned int, function ) @@ -160,6 +160,7 @@ TRACE_EVENT(kvm_cpuid, __field( unsigned long, rbx ) __field( unsigned long, rcx ) __field( unsigned long, rdx ) + __field( bool, found ) ), TP_fast_assign( @@ -168,11 +169,13 @@ TRACE_EVENT(kvm_cpuid, __entry->rbx = rbx; __entry->rcx = rcx; __entry->rdx = rdx; + __entry->found = found; ), - TP_printk("func %x rax %lx rbx %lx rcx %lx rdx %lx", + TP_printk("func %x rax %lx rbx %lx rcx %lx rdx %lx, cpuid entry %s", __entry->function, __entry->rax, - __entry->rbx, __entry->rcx, __entry->rdx) + __entry->rbx, __entry->rcx, __entry->rdx, + __entry->found ? "found" : "not found") ); #define AREG(x) { APIC_##x, "APIC_" #x } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e40a779..ee99fc1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5213,10 +5213,10 @@ static int emulator_intercept(struct x86_emulate_ctxt *ctxt, return kvm_x86_ops->check_intercept(emul_to_vcpu(ctxt), info, stage); } -static void emulator_get_cpuid(struct x86_emulate_ctxt *ctxt, - u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) +static bool emulator_get_cpuid(struct x86_emulate_ctxt *ctxt, + u32 *eax, u32 *ebx, u32 *ecx, u32 *edx, int check_limit) { - kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx); + return kvm_cpuid(emul_to_vcpu(ctxt), eax, ebx, ecx, edx, check_limit); } static ulong emulator_read_gpr(struct x86_emulate_ctxt *ctxt, unsigned reg) -- 2.5.0