[PATCH] KVM: Recover after an arch module load failure

[~andy/linux] / drivers / kvm / kvm_main.c

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 38375e2bb7036df26d90d6b6fec60e43722e8f08..b54caf0ceeb1305a2129177234a745cf079897a5 100644 (file)
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -245,7 +245,8 @@ static void kvm_free_physmem_slot(struct kvm_memory_slot *free,
        if (!dont || free->phys_mem != dont->phys_mem)
                if (free->phys_mem) {
                        for (i = 0; i < free->npages; ++i)
-                               __free_page(free->phys_mem[i]);
+                               if (free->phys_mem[i])
+                                       __free_page(free->phys_mem[i]);
                        vfree(free->phys_mem);
                }
 
@@ -521,12 +522,14 @@ static int kvm_dev_ioctl_create_vcpu(struct kvm *kvm, int n)
        if (r < 0)
                goto out_free_vcpus;
 
-       kvm_arch_ops->vcpu_load(vcpu);
+       r = kvm_mmu_create(vcpu);
+       if (r < 0)
+               goto out_free_vcpus;
 
-       r = kvm_arch_ops->vcpu_setup(vcpu);
+       kvm_arch_ops->vcpu_load(vcpu);
+       r = kvm_mmu_setup(vcpu);
        if (r >= 0)
-               r = kvm_mmu_init(vcpu);
-
+               r = kvm_arch_ops->vcpu_setup(vcpu);
        vcpu_put(vcpu);
 
        if (r < 0)
@@ -1103,6 +1106,51 @@ void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
        }
 }
 
+int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata)
+{
+       u64 data;
+
+       switch (msr) {
+       case 0xc0010010: /* SYSCFG */
+       case 0xc0010015: /* HWCR */
+       case MSR_IA32_PLATFORM_ID:
+       case MSR_IA32_P5_MC_ADDR:
+       case MSR_IA32_P5_MC_TYPE:
+       case MSR_IA32_MC0_CTL:
+       case MSR_IA32_MCG_STATUS:
+       case MSR_IA32_MCG_CAP:
+       case MSR_IA32_MC0_MISC:
+       case MSR_IA32_MC0_MISC+4:
+       case MSR_IA32_MC0_MISC+8:
+       case MSR_IA32_MC0_MISC+12:
+       case MSR_IA32_MC0_MISC+16:
+       case MSR_IA32_UCODE_REV:
+       case MSR_IA32_PERF_STATUS:
+               /* MTRR registers */
+       case 0xfe:
+       case 0x200 ... 0x2ff:
+               data = 0;
+               break;
+       case 0xcd: /* fsb frequency */
+               data = 3;
+               break;
+       case MSR_IA32_APICBASE:
+               data = vcpu->apic_base;
+               break;
+#ifdef CONFIG_X86_64
+       case MSR_EFER:
+               data = vcpu->shadow_efer;
+               break;
+#endif
+       default:
+               printk(KERN_ERR "kvm: unhandled rdmsr: 0x%x\n", msr);
+               return 1;
+       }
+       *pdata = data;
+       return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_get_msr_common);
+
 /*
  * Reads an msr value (of 'msr_index') into 'pdata'.
  * Returns 0 on success, non-0 otherwise.
@@ -1115,7 +1163,7 @@ static int get_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 *pdata)
 
 #ifdef CONFIG_X86_64
 
-void set_efer(struct kvm_vcpu *vcpu, u64 efer)
+static void set_efer(struct kvm_vcpu *vcpu, u64 efer)
 {
        if (efer & EFER_RESERVED_BITS) {
                printk(KERN_DEBUG "set_efer: 0x%llx #GP, reserved bits\n",
@@ -1138,10 +1186,36 @@ void set_efer(struct kvm_vcpu *vcpu, u64 efer)
 
        vcpu->shadow_efer = efer;
 }
-EXPORT_SYMBOL_GPL(set_efer);
 
 #endif
 
+int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data)
+{
+       switch (msr) {
+#ifdef CONFIG_X86_64
+       case MSR_EFER:
+               set_efer(vcpu, data);
+               break;
+#endif
+       case MSR_IA32_MC0_STATUS:
+               printk(KERN_WARNING "%s: MSR_IA32_MC0_STATUS 0x%llx, nop\n",
+                      __FUNCTION__, data);
+               break;
+       case MSR_IA32_UCODE_REV:
+       case MSR_IA32_UCODE_WRITE:
+       case 0x200 ... 0x2ff: /* MTRRs */
+               break;
+       case MSR_IA32_APICBASE:
+               vcpu->apic_base = data;
+               break;
+       default:
+               printk(KERN_ERR "kvm: unhandled wrmsr: 0x%x\n", msr);
+               return 1;
+       }
+       return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_set_msr_common);
+
 /*
  * Writes msr value into into the appropriate "register".
  * Returns 0 on success, non-0 otherwise.
@@ -1865,17 +1939,22 @@ int kvm_init_arch(struct kvm_arch_ops *ops, struct module *module)
 {
        int r;
 
-       kvm_arch_ops = ops;
+       if (kvm_arch_ops) {
+               printk(KERN_ERR "kvm: already loaded the other module\n");
+               return -EEXIST;
+       }
 
-       if (!kvm_arch_ops->cpu_has_kvm_support()) {
+       if (!ops->cpu_has_kvm_support()) {
                printk(KERN_ERR "kvm: no hardware support\n");
                return -EOPNOTSUPP;
        }
-       if (kvm_arch_ops->disabled_by_bios()) {
+       if (ops->disabled_by_bios()) {
                printk(KERN_ERR "kvm: disabled by bios\n");
                return -EOPNOTSUPP;
        }
 
+       kvm_arch_ops = ops;
+
        r = kvm_arch_ops->hardware_setup();
        if (r < 0)
            return r;
@@ -1907,6 +1986,7 @@ void kvm_exit_arch(void)
        unregister_reboot_notifier(&kvm_reboot_notifier);
        on_each_cpu(kvm_arch_ops->hardware_disable, 0, 0, 1);
        kvm_arch_ops->hardware_unsetup();
+       kvm_arch_ops = NULL;
 }
 
 static __init int kvm_init(void)