KVM: x86: only copy XSAVE state for the supported features

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index e5ca72a5cdb6da13617033ad8c0c65c4391d9e2f..e8e2d09dfe7d6f88da0a3acbc4e72fec5c1be2cf 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -586,7 +586,7 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr)
                return 1;
        if ((xcr0 & XSTATE_YMM) && !(xcr0 & XSTATE_SSE))
                return 1;
-       if (xcr0 & ~host_xcr0)
+       if (xcr0 & ~vcpu->arch.guest_supported_xcr0)
                return 1;
        kvm_put_guest_xcr0(vcpu);
        vcpu->arch.xcr0 = xcr0;
@@ -2984,11 +2984,13 @@ static int kvm_vcpu_ioctl_x86_set_debugregs(struct kvm_vcpu *vcpu,
 static void kvm_vcpu_ioctl_x86_get_xsave(struct kvm_vcpu *vcpu,
                                         struct kvm_xsave *guest_xsave)
 {
-       if (cpu_has_xsave)
+       if (cpu_has_xsave) {
                memcpy(guest_xsave->region,
                        &vcpu->arch.guest_fpu.state->xsave,
-                       xstate_size);
-       else {
+                       vcpu->arch.guest_xstate_size);
+               *(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)] &=
+                       vcpu->arch.guest_supported_xcr0 | XSTATE_FPSSE;
+       } else {
                memcpy(guest_xsave->region,
                        &vcpu->arch.guest_fpu.state->fxsave,
                        sizeof(struct i387_fxsave_struct));
@@ -3003,10 +3005,19 @@ static int kvm_vcpu_ioctl_x86_set_xsave(struct kvm_vcpu *vcpu,
        u64 xstate_bv =
                *(u64 *)&guest_xsave->region[XSAVE_HDR_OFFSET / sizeof(u32)];
 
-       if (cpu_has_xsave)
+       if (cpu_has_xsave) {
+               /*
+                * Here we allow setting states that are not present in
+                * CPUID leaf 0xD, index 0, EDX:EAX.  This is for compatibility
+                * with old userspace.
+                */
+               if (xstate_bv & ~KVM_SUPPORTED_XCR0)
+                       return -EINVAL;
+               if (xstate_bv & ~host_xcr0)
+                       return -EINVAL;
                memcpy(&vcpu->arch.guest_fpu.state->xsave,
-                       guest_xsave->region, xstate_size);
-       else {
+                       guest_xsave->region, vcpu->arch.guest_xstate_size);
+       } else {
                if (xstate_bv & ~XSTATE_FPSSE)
                        return -EINVAL;
                memcpy(&vcpu->arch.guest_fpu.state->fxsave,
@@ -5263,7 +5274,7 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
 
        smp_call_function_single(freq->cpu, tsc_khz_changed, freq, 1);
 
-       raw_spin_lock(&kvm_lock);
+       spin_lock(&kvm_lock);
        list_for_each_entry(kvm, &vm_list, vm_list) {
                kvm_for_each_vcpu(i, vcpu, kvm) {
                        if (vcpu->cpu != freq->cpu)
@@ -5273,7 +5284,7 @@ static int kvmclock_cpufreq_notifier(struct notifier_block *nb, unsigned long va
                                send_ipi = 1;
                }
        }
-       raw_spin_unlock(&kvm_lock);
+       spin_unlock(&kvm_lock);
 
        if (freq->old < freq->new && send_ipi) {
                /*
@@ -5426,12 +5437,12 @@ static void pvclock_gtod_update_fn(struct work_struct *work)
        struct kvm_vcpu *vcpu;
        int i;
 
-       raw_spin_lock(&kvm_lock);
+       spin_lock(&kvm_lock);
        list_for_each_entry(kvm, &vm_list, vm_list)
                kvm_for_each_vcpu(i, vcpu, kvm)
                        set_bit(KVM_REQ_MASTERCLOCK_UPDATE, &vcpu->requests);
        atomic_set(&kvm_guest_has_master_clock, 0);
-       raw_spin_unlock(&kvm_lock);
+       spin_unlock(&kvm_lock);
 }
 
 static DECLARE_WORK(pvclock_gtod_work, pvclock_gtod_update_fn);
@@ -6940,6 +6951,10 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
 
        vcpu->arch.ia32_tsc_adjust_msr = 0x0;
        vcpu->arch.pv_time_enabled = false;
+
+       vcpu->arch.guest_supported_xcr0 = 0;
+       vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET;
+
        kvm_async_pf_hash_reset(vcpu);
        kvm_pmu_init(vcpu);