Introduce kvm_cpuid() to perform the leaf limit check and calculate register values, and let kvm_emulate_cpuid() just handle reading and writing the registers from/to the vcpu. This allows us to reuse kvm_cpuid() in a context where directly reading and writing registers is not desired. Signed-off-by: Avi Kivity <avi@xxxxxxxxxx> --- arch/x86/kvm/cpuid.c | 38 ++++++++++++++++++++++++-------------- arch/x86/kvm/cpuid.h | 1 + 2 files changed, 25 insertions(+), 14 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 7df1c6d..44476fb 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -639,33 +639,43 @@ static struct kvm_cpuid_entry2* check_cpuid_limit(struct kvm_vcpu *vcpu, return kvm_find_cpuid_entry(vcpu, maxlevel->eax, index); } -void kvm_emulate_cpuid(struct kvm_vcpu *vcpu) +void kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx, u32 *ecx, u32 *edx) { - u32 function, index; + u32 function = *eax, index = *ecx; struct kvm_cpuid_entry2 *best; - function = kvm_register_read(vcpu, VCPU_REGS_RAX); - index = kvm_register_read(vcpu, VCPU_REGS_RCX); - kvm_register_write(vcpu, VCPU_REGS_RAX, 0); - kvm_register_write(vcpu, VCPU_REGS_RBX, 0); - kvm_register_write(vcpu, VCPU_REGS_RCX, 0); - kvm_register_write(vcpu, VCPU_REGS_RDX, 0); best = kvm_find_cpuid_entry(vcpu, function, index); if (!best) best = check_cpuid_limit(vcpu, function, index); if (best) { - kvm_register_write(vcpu, VCPU_REGS_RAX, best->eax); - kvm_register_write(vcpu, VCPU_REGS_RBX, best->ebx); - kvm_register_write(vcpu, VCPU_REGS_RCX, best->ecx); - kvm_register_write(vcpu, VCPU_REGS_RDX, best->edx); - } - kvm_x86_ops->skip_emulated_instruction(vcpu); + *eax = best->eax; + *ebx = best->ebx; + *ecx = best->ecx; + *edx = best->edx; + } else + *eax = *ebx = *ecx = *edx = 0; + trace_kvm_cpuid(function, kvm_register_read(vcpu, VCPU_REGS_RAX), kvm_register_read(vcpu, VCPU_REGS_RBX), kvm_register_read(vcpu, VCPU_REGS_RCX), kvm_register_read(vcpu, VCPU_REGS_RDX)); } + +void kvm_emulate_cpuid(struct kvm_vcpu *vcpu) +{ + u32 function, eax, ebx, ecx, edx; + + function = eax = kvm_register_read(vcpu, VCPU_REGS_RAX); + ecx = kvm_register_read(vcpu, VCPU_REGS_RCX); + kvm_cpuid(vcpu, &eax, &ebx, &ecx, &edx); + kvm_register_write(vcpu, VCPU_REGS_RAX, eax); + kvm_register_write(vcpu, VCPU_REGS_RBX, ebx); + kvm_register_write(vcpu, VCPU_REGS_RCX, ecx); + kvm_register_write(vcpu, VCPU_REGS_RDX, edx); + kvm_x86_ops->skip_emulated_instruction(vcpu); + trace_kvm_cpuid(function, eax, ebx, ecx, edx); +} EXPORT_SYMBOL_GPL(kvm_emulate_cpuid); diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index 26d1fb4..f449edc 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -17,6 +17,7 @@ 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); static inline bool guest_cpuid_has_xsave(struct kvm_vcpu *vcpu) -- 1.7.10.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html