From b209749f528488c4c0d20a42c0fbcbf49e6933b3 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Mon, 22 Oct 2007 16:50:39 +0200 Subject: KVM: local APIC TPR access reporting facility Add a facility to report on accesses to the local apic tpr even if the local apic is emulated in the kernel. This is basically a hack that allows userspace to patch Windows which tends to bang on the tpr a lot. Signed-off-by: Avi Kivity --- arch/x86/kvm/lapic.c | 21 +++++++++++++++++++++ arch/x86/kvm/x86.c | 25 +++++++++++++++++++++++++ 2 files changed, 46 insertions(+) (limited to 'arch') diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 4076331b01ee..50c3f3a8dd3d 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -551,6 +551,23 @@ static u32 apic_get_tmcct(struct kvm_lapic *apic) return tmcct; } +static void __report_tpr_access(struct kvm_lapic *apic, bool write) +{ + struct kvm_vcpu *vcpu = apic->vcpu; + struct kvm_run *run = vcpu->run; + + set_bit(KVM_REQ_REPORT_TPR_ACCESS, &vcpu->requests); + kvm_x86_ops->cache_regs(vcpu); + run->tpr_access.rip = vcpu->arch.rip; + run->tpr_access.is_write = write; +} + +static inline void report_tpr_access(struct kvm_lapic *apic, bool write) +{ + if (apic->vcpu->arch.tpr_access_reporting) + __report_tpr_access(apic, write); +} + static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset) { u32 val = 0; @@ -568,6 +585,9 @@ static u32 __apic_read(struct kvm_lapic *apic, unsigned int offset) val = apic_get_tmcct(apic); break; + case APIC_TASKPRI: + report_tpr_access(apic, false); + /* fall thru */ default: apic_update_ppr(apic); val = apic_get_reg(apic, offset); @@ -677,6 +697,7 @@ static void apic_mmio_write(struct kvm_io_device *this, break; case APIC_TASKPRI: + report_tpr_access(apic, true); apic_set_tpr(apic, val & 0xff); break; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 513258c797ca..c2b80884447e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -684,6 +684,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_USER_MEMORY: case KVM_CAP_SET_TSS_ADDR: case KVM_CAP_EXT_CPUID: + case KVM_CAP_VAPIC: r = 1; break; default: @@ -1055,6 +1056,15 @@ static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, return 0; } +static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu, + struct kvm_tpr_access_ctl *tac) +{ + if (tac->flags) + return -EINVAL; + vcpu->arch.tpr_access_reporting = !!tac->enabled; + return 0; +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) { @@ -1148,6 +1158,21 @@ long kvm_arch_vcpu_ioctl(struct file *filp, case KVM_SET_MSRS: r = msr_io(vcpu, argp, do_set_msr, 0); break; + case KVM_TPR_ACCESS_REPORTING: { + struct kvm_tpr_access_ctl tac; + + r = -EFAULT; + if (copy_from_user(&tac, argp, sizeof tac)) + goto out; + r = vcpu_ioctl_tpr_access_reporting(vcpu, &tac); + if (r) + goto out; + r = -EFAULT; + if (copy_to_user(argp, &tac, sizeof tac)) + goto out; + r = 0; + break; + }; default: r = -EINVAL; } -- cgit v1.2.3