KVM: Don't assign vcpu->cr3 if it's invalid: check first, set last

[linux-2.6] / drivers / kvm / kvm_main.c

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 4166a08ce5007fca98793f255438905189df698c..5dc60170278241235d34009b6094b63fcd10c7b3 100644 (file)
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -154,8 +154,8 @@ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu)
                return;
 
        vcpu->guest_fpu_loaded = 1;
-       fx_save(vcpu->host_fx_image);
-       fx_restore(vcpu->guest_fx_image);
+       fx_save(&vcpu->host_fx_image);
+       fx_restore(&vcpu->guest_fx_image);
 }
 EXPORT_SYMBOL_GPL(kvm_load_guest_fpu);
 
@@ -165,8 +165,8 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu)
                return;
 
        vcpu->guest_fpu_loaded = 0;
-       fx_save(vcpu->guest_fx_image);
-       fx_restore(vcpu->host_fx_image);
+       fx_save(&vcpu->guest_fx_image);
+       fx_restore(&vcpu->host_fx_image);
 }
 EXPORT_SYMBOL_GPL(kvm_put_guest_fpu);
 
@@ -262,10 +262,6 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
        }
        vcpu->pio_data = page_address(page);
 
-       vcpu->host_fx_image = (char*)ALIGN((hva_t)vcpu->fx_buf,
-                                          FX_IMAGE_ALIGN);
-       vcpu->guest_fx_image = vcpu->host_fx_image + FX_IMAGE_SIZE;
-
        r = kvm_mmu_create(vcpu);
        if (r < 0)
                goto fail_free_pio_data;
@@ -583,7 +579,6 @@ void set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
                }
        }
 
-       vcpu->cr3 = cr3;
        mutex_lock(&vcpu->kvm->lock);
        /*
         * Does the new cr3 value map to physical memory? (Note, we
@@ -596,8 +591,10 @@ void set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
         */
        if (unlikely(!gfn_to_memslot(vcpu->kvm, cr3 >> PAGE_SHIFT)))
                inject_gp(vcpu);
-       else
+       else {
+               vcpu->cr3 = cr3;
                vcpu->mmu.new_cr3(vcpu);
+       }
        mutex_unlock(&vcpu->kvm->lock);
 }
 EXPORT_SYMBOL_GPL(set_cr3);
@@ -615,30 +612,20 @@ EXPORT_SYMBOL_GPL(set_cr8);
 
 void fx_init(struct kvm_vcpu *vcpu)
 {
-       struct __attribute__ ((__packed__)) fx_image_s {
-               u16 control; //fcw
-               u16 status; //fsw
-               u16 tag; // ftw
-               u16 opcode; //fop
-               u64 ip; // fpu ip
-               u64 operand;// fpu dp
-               u32 mxcsr;
-               u32 mxcsr_mask;
-
-       } *fx_image;
+       unsigned after_mxcsr_mask;
 
        /* Initialize guest FPU by resetting ours and saving into guest's */
        preempt_disable();
-       fx_save(vcpu->host_fx_image);
+       fx_save(&vcpu->host_fx_image);
        fpu_init();
-       fx_save(vcpu->guest_fx_image);
-       fx_restore(vcpu->host_fx_image);
+       fx_save(&vcpu->guest_fx_image);
+       fx_restore(&vcpu->host_fx_image);
        preempt_enable();
 
-       fx_image = (struct fx_image_s *)vcpu->guest_fx_image;
-       fx_image->mxcsr = 0x1f80;
-       memset(vcpu->guest_fx_image + sizeof(struct fx_image_s),
-              0, FX_IMAGE_SIZE - sizeof(struct fx_image_s));
+       after_mxcsr_mask = offsetof(struct i387_fxsave_struct, st_space);
+       vcpu->guest_fx_image.mxcsr = 0x1f80;
+       memset((void *)&vcpu->guest_fx_image + after_mxcsr_mask,
+              0, sizeof(struct i387_fxsave_struct) - after_mxcsr_mask);
 }
 EXPORT_SYMBOL_GPL(fx_init);
 
@@ -817,11 +804,14 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
        if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
                goto out;
 
-       mutex_lock(&kvm->lock);
-       kvm_mmu_slot_remove_write_access(kvm, log->slot);
-       kvm_flush_remote_tlbs(kvm);
-       memset(memslot->dirty_bitmap, 0, n);
-       mutex_unlock(&kvm->lock);
+       /* If nothing is dirty, don't bother messing with page tables. */
+       if (any) {
+               mutex_lock(&kvm->lock);
+               kvm_mmu_slot_remove_write_access(kvm, log->slot);
+               kvm_flush_remote_tlbs(kvm);
+               memset(memslot->dirty_bitmap, 0, n);
+               mutex_unlock(&kvm->lock);
+       }
 
        r = 0;
 
@@ -2356,6 +2346,9 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 
        preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
+       /* We do fxsave: this must be aligned. */
+       BUG_ON((unsigned long)&vcpu->host_fx_image & 0xF);
+
        vcpu_load(vcpu);
        r = kvm_mmu_setup(vcpu);
        vcpu_put(vcpu);
@@ -2468,7 +2461,7 @@ struct fxsave {
 
 static int kvm_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-       struct fxsave *fxsave = (struct fxsave *)vcpu->guest_fx_image;
+       struct fxsave *fxsave = (struct fxsave *)&vcpu->guest_fx_image;
 
        vcpu_load(vcpu);
 
@@ -2488,7 +2481,7 @@ static int kvm_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 
 static int kvm_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
 {
-       struct fxsave *fxsave = (struct fxsave *)vcpu->guest_fx_image;
+       struct fxsave *fxsave = (struct fxsave *)&vcpu->guest_fx_image;
 
        vcpu_load(vcpu);
 
@@ -3110,6 +3103,7 @@ int kvm_init_arch(struct kvm_arch_ops *ops, unsigned int vcpu_size,
                  struct module *module)
 {
        int r;
+       int cpu;
 
        if (kvm_arch_ops) {
                printk(KERN_ERR "kvm: already loaded the other module\n");
@@ -3131,6 +3125,14 @@ int kvm_init_arch(struct kvm_arch_ops *ops, unsigned int vcpu_size,
        if (r < 0)
                goto out;
 
+       for_each_online_cpu(cpu) {
+               smp_call_function_single(cpu,
+                               kvm_arch_ops->check_processor_compatibility,
+                               &r, 0, 1);
+               if (r < 0)
+                       goto out_free_0;
+       }
+
        on_each_cpu(hardware_enable, NULL, 0, 1);
        r = register_cpu_notifier(&kvm_cpu_notifier);
        if (r)
@@ -3177,6 +3179,7 @@ out_free_2:
        unregister_cpu_notifier(&kvm_cpu_notifier);
 out_free_1:
        on_each_cpu(hardware_disable, NULL, 0, 1);
+out_free_0:
        kvm_arch_ops->hardware_unsetup();
 out:
        kvm_arch_ops = NULL;